Preterit vs Imperfect (How to Distinguish)
http://www.youtube.com/watch?v=3_v79t_QAA8&feature=youtube_gdata_player

Preterit vs Imperfect (Interrupting Actions)
http://www.youtube.com/watch?v=8T1a5G75uY4&feature=youtube_gdata_player

Preterit vs Imperfect (English Translations)
http://www.youtube.com/watch?v=W0-otdLdDoc&feature=youtube_gdata_player







Querer
Preterit: i wanted to [and did]
Preterit negative: i didn't want to [i refused]
imperfecto: i wanted to ... But who knows if i did

Poder
Preterit: i was able to run a marathon and did
Imperfecto: i was able to run a marathon but who knows if i did

Saber
Preterit: i found out...
Imperfecto: i knew where...

Conocer
Preterit: i met him
Imperfecto: i knew him
++++++++++

Preterit

Saying what you did and where went.

Ayer, anoche, el mes pasado, hace dos días
++++++++++

imperfect

Describing how things used to be.

May need to use subject pronouns since yo and el endings are same:
Aba, aba
Ía, ía

Siempre hablábamos en clase
We always spoke in class.
We always used to speak in class.
We would always speak in class.




Preterit versus imperfect
http://www.spanishdict.com/topics/show/64

differences and signifier phrases

Overview

Many students have trouble knowing when to use the preterit past or the imperfect past since they both refer to actions in the past. There are several general rules to follow as well as phrases to look out for. Many phrases use only one tense or the other, so memorizing them is very helpful in figuring out whether the following verb will be in the preterit or imperfect.

General Preterit Uses

Generally, the preterit is used for actions considered completed, actions that have definite beginning and end points. These can be actions that can be viewed as single events, actions that were part of a chain of events, actions that were repeated a very specific number of times, or actions that specifically state the beginning and end of an action.

Fui al baile anoche. (I went to the dance last night.)
Caminé al mercado, compré unos plátanos, y regresé a casa. (I walked to the market, bought some bananas, and returned home.)
Te llamó tres veces. (He called you three times.)
Hablé con mi madre de las dos hasta las tres. (I spoke with my mother from two o’clock until three o’clock.)

Useful Phrases that Trigger the Preterit

Some words and phrases are very helpful in indicating specific time frames and therefore signal the use of the preterit.

a esa hora at that time
anoche last night
ante anoche the night before last
ante ayer the day before yesterday
ayer yesterday
ayer por la tarde yesterday afternoon
ayer por la noche last night
la semana pasada last week
ayer al mediodía yesterday at noon
ayer por la mañana yesterday morning
desde el primer momento from the first moment

durante (tres) siglos for (three) centuries
entonces then
el año pasado last year
el (lunes) pasado last (Monday)
el mes pasado last month
el otro día the other day
en ese momento at that moment
esta mañana this morning
esta tarde this afternoon
hace (dos) años/días (two) years/days ago
hoy por la mañana this morning
la semana pasada last week
una vez one time

Verbs that are Preterit by Nature

Some verbs are preterit by nature since they have a very definite beginning and ending.

casarse to get married
cumplir años to turn a certain age
darse cuenta de to realize
decidir to decide
descubrir to discover
graduarse to graduate
llegar to arrive
morir to die
nacer to be born
salir to leave

General Imperfect Uses

Generally used for actions in the past that do not have a definite end. These can be actions that are not yet completed or refer to a time in general in the past. They can be actions that were repeated habitually, actions that set the stage for another past tense event, for time and dates in the past, for telling a person’s age in the past, to describe people (characteristics) in the past, and to communicate mental or physical states in the past. For descriptions, think of describing what people used to be like in a photograph.

Cuando era niña, jugaba con muñecas. (When I was a child, I played with dolls.)
Los chicos hablaban en español. (The boys used to speak in Spanish.)
Estaba durmiendo cuando el teléfono sonó. (I was sleeping when the telephone rang.)
Cuando tenía tres años, era muy pequeño. (When he was three years old, he was very small.)

Useful Phrases that Trigger the Imperfect

a menudo often
a veces sometimes
algunas veces at times
cada día/semana/mes/año every day/week/month/year
con frecuencia frequently
casi nunca almost never
de vez en cuando once in a while
en aquella época at that time
frecuentemente frequently
generalmente usually
mientras while
muchas veces many times
mucho a lot
nunca never
por lo general generally
por un rato for a while
rara vez rarely
siempre always
tantas veces so many times
todo el tiempo all the time
todas las semanas every week
todos los años every year
todos los días everyday
varias veces several times



Preterite

Preterit versus imperfect

Spanish uses two different conjugations to communicate ideas that are given in context in English. Regarding the preterite, think action that happened at a specific time. It refers to completed action.
When it comes to the imperfect think that it talks about action that occurred at a general time in the past (perfect equaling uncompleted). It refers to habits or actions without definite beginnings or endings.

While the imperfect handles all habitual, continuous, or repetitive actions and verbs denoting a state of being, preterit covers pretty much whatever is left - actions that were performed and also concluded well within the past.

In simpler terms, preterit is the tense used in Spanish for past actions that are seen as completed.
Completion here implies that the event had a definite beginning and an equally definite end.

This is in sharp contrast to the imperfect tense where there is no such well-defined completion, hence the name.

Some examples illustrating the preterit tense:

I ate a taco last night (preterit because I started and finished eating well within last night).

Juan spoke for 5 hours (preterit because the act of speaking did end after 5 hours).

It began to rain in the evening (preterite because even though the rain could have lasted indefinitely, the event in question - the beginning of rain - had a specific time of occurrence,evening).

Ana ran through the woods (preterit because Ana ran only once and this wasn't a repetitive or habitual action).

The preterite tense is used to refer to actions that occurred at a fixed point in time.
I called at 1:00. Llamé a la una.

The preterite tense is also used to refer to actions in the past that were performed a specific number of times.
I called you twice. Te llamé dos veces.

The preterite tense is also used to refer to actions that occurred during a specific enclosed period of time.
He lived there for 5 years. Él vivió allí por cinco años.

The preterite is also used for actions that are part of a chain of events.
I bought a hat, sat down on a bench and fell asleep. Compré un sombrero, me senté en un banco y me dormí.

The preterite is also used for sudden changes of mood, feelings or opinions.
At that moment, I was not afraid. En ese momento, no tuve miedo.

The preterite is frequently associated with words that pinpoint a particular occasion or specific point of time in the past.

Words that point to a specific point of time in the past would indicate the preterite:

ayer
ayer por la mañana
ayer por la tarde
anteayer
anoche
desde el primer momento
después
durante dos siglos
el año pasado
el lunes por la noche
el mes pasado
el otro día
en ese momento
entonces
esta mañana
esta tarde
hace dos días, años
la semana pasada

If the action is in the past, and you can determine precisely when it occurred, or how many times it occurred, then you will use the preterite.

The preterit tense (el pretérito) is one of several past tenses in Spanish and it is used to describe actions completed at one point in the past or that lasted a specific amount of time in the past and are now completed. The preterit is not used to describe habitual or continuous actions in the past with no specific ending or beginning. The imperfect tense is used for these instances. If the habitual action does have a specific beginning and end, the preterit can be used.

Note that ser and ir share the exact same forms in the preterit.

Many verbs in the preterite are irregular and must be memorized. Here are a few:
Note: This is not a typo; ser and ir do have identical conjugations in the preterite!
ser: fui, fuiste, fue, fuimos, fueron
ir: fui, fuiste, fue, fuimos, fueron
dar: di, diste, dio, dimos, dieron
hacer: hice, hiciste, hizo, hicimos, hicieron

Uses of the Preterit

In general, the preterit is used to describe completed actions in the past at specific points in time.

1. To Indicate a Single Event that Took Place in the Past

These actions began and ended in the past. They are usually verbs that communicate an instant change in the action.
• Compré un coche nuevo. (I bought a new car.)
• Ben y Cristina se casaron. (Ben and Cristina got married.)
• Roberto nació. (Roberto was born.)

2. To Indicate an Action that Happened at or for a Specific Amount of Time

These actions are completed at a definite moment in the past. They are easy to spot since they usually have a time frame in the sentence.
• Regresé anoche a la medianoche. (I returned last night at midnight.)
• Vivió en Perú por tres meses. (He lived in Peru for three months.)
• Leíste este libro cinco veces. (You read this book 5 times.)

3. To Narrate Individual Events

This is common in relating a story line where there are multiple actions presented.
• Me levanté, me vestí, y salí para la fiesta. (I got up, got dressed, and left for the party.)
• Tú entraste, bebiste un vaso de agua y comiste una hamburguesa. (You came in, drank a glass of water, and ate a hamburger.)

4. To Indicate the Beginning or End of an Action in the Past

• Empezó a nevar. (It began to snow.)
• La película terminó con una sorpresa. (The movie ended with a surprise.)

Preterit sentence examples:

Los muchachos compraron un regalo para su amigo.
¿Hablaste con el abogado ayer?
María tomó la medicina.
Yo llevé la carta a la oficina.
¿Preparaste el almuerzo?
Los muchachos lavaron la ropa.
Yo pinté las paredes.
¿Limpiaste la cocina?
Juan cerró la ventana.
Nosotros cambiamos un cheque en el banco.
Los muchachos estudiaron la lección.
Yo escuché la música.

Notice that when we have a human direct object, we have to use the preposition "a", even though we wouldn't translate it as the English word "to". It's called the "personal" use of "a", since it refers to persons used as direct objects.

¿Visitaste a tu abuela?

++++hace + time expression + preterite ago
Hace tres días no dormí bien.
I didn't sleep well three days ago.



PRETERITE

The preterite tells us specifically when an action took place.
The imperfect tells us in general when an action took place.
Generally speaking, the preterite is used for actions in the past that are seen as completed. Use of the preterite tense implies that the past action had a definite beginning and definite end.
Juan habló de la una hasta las dos.
Juan spoke from one until two o'clock.
(clearly stated beginning and end)
It is important to realize that the beginning and the end may not always be clearly stated.
Juan habló dos horas.
Juan spoke for two hours.
(implied beginning and end)
Juan habló con la estudiante.
Juan spoke with the student.
(implied beginning and end)

Some words and phrases indicate specific time frames, and therefore signal the use of the preterite.
ayer (yesterday)
anteayer (the day before yesterday)
anoche (last night)
desde el primer momento (from the first moment)
durante dos siglos (for two centuries)
el otro día (the other day)
en ese momento (at that moment)
entonces (then)
esta mañana (this morning)
esta tarde (this afternoon)
la semana pasada (last week)
el mes pasado (last month)
el año pasado (last year)
hace dos días, años (two days, years ago)
ayer por la mañana (yesterday morning)
ayer por la tarde (yesterday afternoon)

The preterite is used in the following situations:
For actions that can be viewed as single events
For actions that were repeated a specific number of times
For actions that occurred during a specific period of time
For actions that were part of a chain of events
To state the beginning or the end of an action



Verbs That Change Meaning in Preterite and Imperfect Tenses

In keeping with the differences mentioned between the two tenses, some verbs change meaning when conjugated in the imperfect versus the preterite. This gives a further clue to how different ideas are expressed in Spanish versus English.

For example: Conociste a mi jefe el año pasado. You met my boss last year. Cuando vivías allí, conocías mejor Roma. When you lived there, you knew Rome better.

Notice how the first sentence describes a specific action that happened once in the past, while the second is much more general.

Here are a couple more examples:
Anoche, quiso bailar tango. Last night I tried to dance the tango. Quería bailar tango. I wanted to dance the tango.
Supimos que no era verdad. We found out it wasn't true. Sabíamos que no era verdad. We knew it wasn't true.




++++++++++
Some verbs actually change meaning, depending upon whether they are used in the preterite or the imperfect. This is not surprising, since the difference in meaning can be traced back to the different way in which these two past tenses are used.

conocer
Conocí a Juan hace cinco años.
I met Juan five years ago.
(completed action)
En aquella época conocíamos muy bien la ciudad.
At that time we knew the city very well.
(no definite beginning or end)

querer
María quiso comprar la casa.
Maria tried to buy the house.
(completed action)
Juan quería comprar la casa.
Juan wanted to buy the house.
(no definite beginning or end)

no querer
María no quiso comprar la casa.
Maria refused to buy the house.
(completed action)
Juan no quería comprar la casa.
Juan did not want to buy the house.
(no definite beginning or end)

saber
María lo supo ayer.
Maria found out yesterday.
(completed action)
Juan sabía que María venía.
Juan knew that Maria was coming.
(no definite beginning or end)

poder
María pudo levantar la mesa.
Maria succeeded in lifting the table.
(completed action)
Juan podía participar en la manifestación.
Juan was able to participate in the demonstration.
(no definite beginning or end)

tener
María tuvo una carta de su mamá.
Maria received a letter from her mom.
(completed action)
Juan tenía un coche nuevo.
Juan used to have a new car.
(no definite beginning or end)







IMPERFECT

Spanish uses two different conjugations to communicate ideas that are given in context in English. Regarding the preterite, think action that happened at a specific time. It refers to completed action.
When it comes to the imperfect think that it talks about action that occurred at a general time in the past (perfect equaling uncompleted). It refers to habits or actions without definite beginnings or endings.

I ate tacos when I was in Mexico (imperfect because I am implying eating as a habitual action in the past; I used to eat tacos when I was in Mexico).

She was beautiful (imperfect because being beautiful is a state of being, a characteristic, a trait and the trait hasn't been implied to have changed in the past; this can also be rendered as "she used to be beautiful," a tell-tale sign of the imperfect tense).

Imperfect is the tense we invoke in Spanish whenever we are dealing with past actions that were either incomplete or repetitive; basically, anything that could otherwise be expressed into English with a "used to". Here are some illustrations:

I went to Yale (what I essentially mean here is that I used to go to Yale for my studies; a repetitive action)

I was eating street food every day (I used to eat street food everyday; habitual action)

Juan was sick (he was sick for an undefined period of time; hence, this can be considered an imperfect action like any other statement on feelings or state)

We were returning when we saw Enrique (the act of returning is imperfect in nature because it's incomplete)

My father often drove me to school (my father used to drive me to school; a repetitive action regardless of its frequency)

Every year, the entire family would come together on the Day of the Dead (This line, again, can be rendered using a "used to" and hence becomes a repetitive action)
++++

El Imperfecto
http://roble.pntic.mec.es/acid0002/index_archivos/Gramatica/imperfecto_indicativo.htm

El imperfecto del indicativo se usa para:

Describir acciones continuas

Acciones continuas son acciones que se pueden repetir o continuar por un período de tiempo indeterminado.
Por ejemplo, en la frase: "El hombre dormía", la acción de dormir no tiene límites temporales y es posible extenderla hasta cualquier cantidad de tiempo.
En esta frase, lo importante es la acción en sí y no cuándo ocurre el suceso.
A veces se puede sustituir el progresivo para distinguir una acción contínua.

Ejemplos:
El chico miraba a la joven.
El chico estaba mirando a la joven.
Mi padre leía un libro escrito por Ganivet.
Mi padre estaba leyendo un libro escrito por Ganivet.

Describir acciones repetidas y habituales

Acciones repetidas y habituales o las que pasan por costumbre, emplean el imperfecto.
A menudo, una oración que relata una acción habitual emplea un adverbio o locución adverbial que infiere repetición, tales como todos los días, cada miércoles, como siempre, etc.

Ejemplos:
Cuando era joven, íbamos al cine todos los sábados.
Mi madre siempre llegaba tarde a las citas.

Descripciones sin principio y/o fin

Una descripción general con ser o estar sin referencia a ningún límite temporal emplea el imperfecto.

Ejemplos:
Su hermana mayor era más alta que él.
La casa de mis padres era muy chica.
Estábamos en España el año pasado.

La edad y la hora

Se emplea el imperfecto para expresar la edad o la hora en el pasado.

Ejemplos:
Su abuela tenía 93 años cuando murió.
Mi madre sólo tenía 10 años en 1960.
Eran las dos en punto cuando llegaron.

Descripciones de procesos mentales y estado físico

Se emplea el imperfecto para describir un proceso mental (pensar, querer, esperar) o un estado físico (tener hambre, sed, frío, etc.), siempre y cuando no se desee indicar un cambio en la situación.

Ejemplos:

Esperábamos una buena nota en el examen.
Amada quería comprar un nuevo vestido.
¡No lo sabía!
Alicia pensaba que Ángel era muy guapo.
¡Qué frío tenía en Alaska!
Al terminar el partido el futbolista estaba muy cansado.

Se emplean estos verbos en el pretérito para indicar que se terminó o se resolvió la condición.

Ejemplos:

Quise ir también.
Tuvo mucha hambre.
Estuvieron muy cansados.
Y, sí, lo hice.
Pero, entonces comió una cena magnífica.
Y, por eso, durmieron un par de horas.

Proveer fondo para acciones pretéritas

En una oración compuesta (una que contiene dos verbos ó más), el verbo que provee fondo para una acción pretérita está en el imperfecto.

Ejemplos:

El hombre estaba en el baño cuando sonó el teléfono.
Mi hermano veía la tele cuando, de repente, oyó una explosión.




Uses of the Imperfect Tense

In general, the imperfect can translate to what someone was doing or used to do. It sets the background knowledge or scenery for a story.

1. Actions Repeated Habitually

These are the activities that you did over and over for a long period of undetermined time.
• Almorzábamos cada día. (We used to eat lunch together every day.)
• Todos los sábados las mujeres iban de compras. (Every Saturday the ladies would go shopping.)

2. Actions that Set the Stage for other Actions

The imperfect verb is interrupted by a preterite verb.
• Estaba durmiendo cuando el teléfono sonó. (I was sleeping when the telephone rang.)
• Estaba cocinando la cena cuando entré la casa. (He was cooking dinner when I came in the house.)

3. Telling Time and Dates in the Past

• Eran las tres de la tarde. (It was three o´clock in the afternoon.)
• Era el jueves, el 9 mayo. (It was Thursday, the 19th of May.)

4. Describing a Scene or Person in the Past

• La niña tenía 4 años. (The little girl was 4 years old.)
• Mi profesor era alto y tenía el pelo ondulado. (My professor was tall and had wavy hair.)
• El campo era bello. (The countryside was beautiful.)
• Hacía calor esa noche. (It was hot that night.)

5. Describing Mental/Emotional States or Desires in the Past

• Me sentía feliz con mi trabajo nuevo. (I was happy with my new job.)
• Quería mudarme a otro país. (I wanted to move to another country.)



The imperfect tense is used to refer to actions in the past that occurred repeatedly.
I used to walk every day.
Yo caminaba cada día.

The imperfect tense is also used to refer to actions in the past that occurred over an extended period of time.
I used to eat paella frequently.
Yo comía frecuentemente paella.

The imperfect tense is also used to "set the stage" for an event that occurred in the past.
We were coming home when we saw Juan.
Veníamos para casa cuando vimos a Juan.

Actions which are not physical, that is feelings and mental actions, usually use the imperfect tense.
Juan was feeling sick.
Juan estaba enfermo.

The imperfect is frequently associated with phrases that describe the frequency of past actions.
Words that express repetitive time or non-specific time would indicate the imperfect:

a menudo
a veces
cada día
cada año
con frecuencia
de vez en cuando
en aquella época
frecuentemente
generalmente
muchas veces
mucho
normalmente
nunca
por un rato (for awhile)
siempre
tantas veces (so many times)
todas las semanas
todos los años: every year
todos los días
todo el tiempo (all the time)
varias veces

Only three verbs are irregular in the imperfect:
Ser: era, eras, era, éramos, eran
Ver: veía, veías, veía, veíamos, veían
Ir: iba, ibas, iba, íbamos, iban




What follows if from the document on my laptop entitled "Past Tenses"

IMPERFECT

The imperfect tells us in general when an action took place.

Generally speaking, the imperfect is used for actions in the past that are not seen as completed. Use of the imperfect tense implies that the past action did not have a definite beginning or a definite end.

Las chicas hablaban en inglés.
The girls used to speak in English.
(no definite beginning or end)

Other words and phrases indicate repetitive, vague or non-specific time frames, and therefore signal the use of the imperfect.

a menudo (often)
a veces (sometimes)
cada día (every day)
cada semana (every week)
cada mes (every month)
cada año (every year)
con frecuencia (frequently)
de vez en cuando (from time to time)
en aquella época (at that time)
frecuentemente (frequently)
generalmente (usually)
muchas veces (many times)
mucho (a lot)
nunca (never)
por un rato (for awhile)
siempre (always)
tantas veces (so many times)
todas las semanas (every week)
todos los días (every day)
todo el tiempo (all the time)
varias veces (several times)

The imperfect is used in the following situations:

For actions that were repeated habitually
For actions that "set the stage" for another past action
For telling time
For stating one's age
For mental states (usually)
For physical sensations (usually)
To describe the characteristics of people, things or conditions



Hubo versus Habia There were

Many students get confused on “what is the difference between HUBO and HABIA?” Remember that the difference between simple past tense and imperfect tense is: simple past tense expresses defined actions, and imperfect tense describes undefined actions and repetitive actions.

El año pasado hubo muchos accidentes en la carretera nueva. – Last year there were many accidents on the new highway.

Solamente había una escuela en mi pueblo cuando yo era niño. – There was only one school in my town when I was a child.
Cuando llegamos al banco había cinco personas esperando. – When we got to the bank, there were five people waiting.
Recuerdo que cuando yo era niña casi siempre había exámenes sorpresa en la clase de matemáticas. – I remember when I was a child, there was always surprise exams in math class.



PRESENT PERFECT

The present perfect tense is frequently used for past actions that continue into the present, or continue to affect the present.
He estado dos semanas en Madrid.
I have been in Madrid for two weeks.
Diego ha sido mi amigo por veinte años.
Diego has been my friend for 20 years.

The present perfect tense is often used with the adverb "ya".
Ya han comido.
They have already eaten.
La empleada ya ha limpiado la casa.
The maid has already cleaned the house.




PAST PERFECT

The past perfect tense is used when a past action was completed prior to another past action.

Expressions such as "ya", "antes", "nunca", "todavía" and "después" will often appear in sentences where one action was completed before another.
Cuando llegaron los padres, los niños ya habían comido.
When the parents arrived, the children had already eaten.
Yo había comido antes de llamarles.
I had eaten prior to calling them.

This idea of a past action being completed before another past action need not always be stated; it can be implied.
Juan había cerrado la ventana antes de salir. (stated) Juan had closed the window before leaving.
Juan había cerrado la ventana. (implied) Juan had closed the window.

Preterite vs perfect
When do you use the preterite and when do you use the perfect tense in Spanish?
http://www.espanol-ingles.com.mx/spanish-grammar/verbs_choosing_preterite_perfect.shtml
The distinction between the perfect tense and the preterite in Spanish is largely similar to English. In other words:
the Spanish preterite or simple past is largely used where English uses simple past forms such as took, gave; the Spanish perfect tense is largely used where English would also use a perfect tense (have taken, have given).
In both English and Spanish, there are some regional differences in the usage of the two tenses. But generally speaking, there are a few differences between English and Spanish use of the preterite and perfect tense that we can point out here.

Questioins involving yet/now translated as ya plus preterite

A common pattern in English (at least in British English) is to use a perfect tense in questions such as:
have you finished now?
have you done your homework yet?
have you found your pen yet?

In Spanish, a common pattern is to use the preterite with ya:
¿ya terminaste?
have you finished (now)?
¿ya hiciste tu tarea de español?
have you done your Spanish work yet?
¿ya encontraste tu pluma?
have you found your pen yet?

However, if ya is removed, it is often possible to use the perfect as in English, leading to alternatives such as:
¿ya le diste de comer?
or:
¿le has dado de comer?
have you fed her yet?

Sentences with ya meaning already
A situation occurs with sentences such as the following, where English uses the perfect to express 'relevance to the present', whereas Spanish appears to favour the preterite, perhaps to express'completion':
ya llegaron mis hermanos
my brothers have already got here

Preterite to signal the impossibility of an event with present relevance

In both English and Spanish perfect generally signals relevance to the present. For example, when you ask have you seen my keys?, the perfect tense emphasises the fact that the speaker needs the keys now, and also suggests that if the person hasn't found seen the keys yet, there's a chance that they still might in the future. Contrast this with a question such as did you see my keys when you were in the bathroom?, which suggests that the person won't have an opportunity to see the keys again now they've left the bathroom. In other words, the person asking the question views the opportunity to see the keys as a "completed event".

In English, there are cases where "present relevance" appears to override the notion of "completed event". For example, consider these sentences:

(a) let's wait a few more minutes: my brother hasn't arrived
(b) we won't be able to go now: my brother hasn't arrived
(b') ??we won't be able to go now: my brother didn't arrive
In (a), there's an implication that the speaker's brother may still arrive. But in (b) the implication is that the brother will never arrive. Despite this notion of "completed, past opportunity", the preterite as in (b') would be an odd choice (at least in British English). It appears that in English, the notion of "present relevance" prevails, and so the perfect is used.
Now, case (a) would generally be translated into Spanish using the perfect tense as you might expect:
esperemos unos minutos más: no ha llegado mi hermano
let's wait a few more minutes: my brother hasn't arrived yet
But in the case of (b), it would be usual in Spanish to use the preterite to signal the idea of "has not arrived and never will". That is, in Spanish, "present relevance" doesn't necessarily prevail as in English in this case:
ya no podremos ir: no llegó mi hermano
we won't be able to go now: my brother hasn't arrived [lit: "...didn't arrive" ]
(Note that it is also possible in Spanish to say ...no ha llegado...in the second case.)

The "perfect of recency"?
Butt & Benjamin (2000:223) give some examples of what they term the "perfect of recency", in which the perfect is used to denote a recent event in Spanish where we might otherwise expect the preterite.
For example:
la he visto hace un momento
I saw her a moment ago (their translation)
Now, it is true that in this "bare" form, the perfect would be unusual in English.
However, if we add the word just, the perfect becomes acceptable:
I've seen her just a moment ago
In other cases, we could view the use of the perfect to denote "recency" as actually being the equivalent of adding just, just then etc in English:
¿qué has dicho?
what did you just say?

The authors mention that this use of the perfect is less common in Latin America. In Mexico at least, the less acceptable examples appear to be specifically those without an explicit time reference such as hace un momento.



He vivido vs viví

"Cuanto tiempo llevas viviendo en Costa Rica?" "He vivido en Costa Rica durante tres años"
He vivido en Costa Rica durante tres anos.
I've lived in Costa Rica for three years (and I still live there)
Me he roto la pierna. (I have broken my leg, I can't walk now)
the use of past participle indicates that the action began in the past but it hasn't finished
+++++++++
"Alguna vez has vivido afuera de los EEUU?" "Sí, viví en Costa Rica durante tres años"
Vivi en Costa Rica durante tres anos.
I lived in Costa Rica for three years (but now I live somewhere else)
Me rompí la pierna. (when I was a child, now everything is fine)
the use of simple past indicates that the action began and finished in the past





When to use the imperfect tense in Spanish?
http://www.espanol-ingles.com.mx/spanish-grammar/verbs_imperfect_usage.shtml
Of all the tenses in Spanish, the imperfect tense has arguably the simplest forms and the fewest irregularities. The problems that often arise with the imperfect tense in Spanish have more to do with when to use it than how.
At least these problems arise:
1. When do you use the imperfect tense as opposed to other past tenses such as the preterite?
2. When do you use the simple vs continuous form of the imperfect (caminaba vs estaba caminando), since both can have a meaning of was walking? (See the imperfect continuous section for more information and exercises on this form.)
3. Combining these problems, when do you use the imperfect continuous vs preterite continuous, which both generally translate as was/were ...ing? That is, when to say estaba caminando vs estuvo caminando?

In many cases, which tense used is slightly arbitrary, because the choice of tense can depend on the emphasis that the speaker/author wants to place.
But in general:
a. the preterite focusses on the completion or endpoint of an event/state;
b. the imperfect focusses on the start or middle of an event/state;
c. the choice between continuous vs simple is often arbitrary, with the continuous being preferred to express "ongoingness" (see below).

Given these generalities, here are some common uses of the imperfect vs other competing Spanish past tenses:

1. Notion of used to..., once ...-ed, especially without mentioning a specific end point in time.
Tense: Imperfect (simple)
Example: vivíamos en una casa más grande
we used to live/once lived in a larger house

2. Describing an ungoing event but without viewing its duration/endpoint
Often the 'background' to another 'simple past' event; often was/were ...ing in English
Tense: Imperfect (simple or continuous)
Example: estaba viendo la tele cuando él llegó
or: veía la tele cuando...
I was watching TV when he arrived

3. Describing the beginning of an event/action
Similarly, English often uses was/were ...ing
Tense: Imperfect (simple or continuous)
Example: estaba saliendo de la casa cuando llamó
Or: salía de la casa...
I was leaving the house when he rang

4. Describing an ongoing state/condition
continuous forms tend not to be used with these types of verb in English or Spanish, so simple past often used in English (but note was going to...)
Tense: Imperfect (simple)
Example: no sabía si iba a venir
I didn't know whether he was going to come
no tenía dinero para comprarlo
I didn't have any money to buy it
querían llegar antes de las dos
they wanted to get there before two o'clock

5. Describing an ongoing event but with a specific duration and/or endpoint
Tense: Preterite (simple or continuous possible)
Choice of simple/continuous similar to English
Example: estuvimos caminando durante tres horas
we were walking for three hours
allí viví hasta la edad de trece años
I lived there until I was thirteen

6. Describing an event with an endpoint or "outcome"
Tense: Preterite
Example: ¿tuviste tiempo para comprarlo?
did you have time to buy it? (i.e. "did you buy it?")
no pude hacerlo
I wasn't able to do it, I couldn't do it ("...and I'm no longer trying to at this moment")
no quiso venir
she didn't want to come (i.e. "she didn't come")

7. Telling the time (in the past)
Tense: Imperfect (simple)
Example: eran las cuatro (it was four o'clock)



Now, let's look at a couple of dilemmas that spring up particularly for English speakers: when to use simple vs continuous imperfect forms, and the difference between estaba/estuvo caminando (that is, the imperfect continuous vs preterite continuous).

When to use the imperfect:
simple vs continuous and imperfect vs preterite continuous
http://www.espanol-ingles.com.mx/spanish-grammar/verbs_imperfect_usage_2.shtml

On the previous page, we summarized imperfect tense usage compared to other tense uses in Spanish. Here, we'll look at a couple of specific dilemmas that spring up around the imperfect tense.

The problem that essentially springs up particularly for English-speaking learners is that there are "too many forms" in Spanish that can translate was/were ...ing. In Spanish, each of the imperfect and preterite can occur in either simple or continuous forms, giving the following four combinations:

Imperfect Simple: caminaba
Imperfect Continuous: estaba caminando
Preterite Simple: caminó
Preterite Continuous: estuvo caminando

The choice between these is sometimes confusing for English speakers because all the forms in italics (i.e. all except for caminó) are frequently translated as "was walking". So what's the difference?

Simple vs continuous: caminaba vs estaba caminando:

There are many cases where the simple and continuous imperfect tense forms are more or less interchangeable. In general:

a. the continuous forms (estaba caminando etc) appear to be slightly more common when the idea is genuinely "in the middle of ...ing", but both forms are possible with this meaning;

b. with the habitual ("used to...") meaning, the simple imperfect tense form is generally used;

c. there are a few verbs that Spanish speakers don't generally use in the continuous form as they tend to refer to fairly permanent "states".
This last point refers to verbs such as parecer ("to look, appear"), faltar/sobrar ("to be lacking").
For example:

ya parecía cansada cuando llegué
(Not: estaba pareciendo)
"She was already looking tired when I arrived"

nos sobraba comida antes de que él llegara
(Not: nos estaba sobrando)
"We had a surplus of food before he arrived"

Imperfect vs preterite: estaba/estuvo caminando

Both of these forms are commonly translated by was/were ...ing in English. They both refer to actions that are viewed as being "drawn out" over a period of time. But the preterite (i.e. estuvo caminando etc) also views the action as completed. So it tends to be used when the speaker wants to emphasise that an action "went on" for a period of time, but where they also mention a phrase such as durante X horas, toda la mañana, hasta ayer etc: that is, a phrase that delimits the action.

Compare, for example:
estaba trabajando cuando llegué
he was working when I arrived
estuvo trabajando toda la noche
he was working all night

In the first case, the imperfect (continuous) is used as the speaker doesn't actually state when the person stopped working, just that they were "in the middle of" working at that point. In the second case, the speaker actually delimits the period over which the person was working.

Note that the imperfect is generally used to describe a repeated action that occurred within a delimited time (e.g. "all night") but where overall the sequence of actions is not delimited. For example: "estaba trabajando toda la noche" would generally imply that the person repeatedly worked all night. That is, they were working every night over a non-specified series of nights.



Will you please explain the difference between the past perfect, preterite and imperfect tenses?
http://answers.yahoo.com/question/index?qid=20090209095453AA7V0Ob

The past perfect tense is used when a past action was completed prior to another past action. Expressions such as "ya", "antes", "nunca", "todavía" and "después" will often appear in sentences where one action was completed before another
Cuando llegaron los padres, los niños ya habían comido.
When the parents arrived, the children had already eaten.
Yo había comido antes de llamarles.
I had eaten prior to calling them.
This idea of a past action being completed before another past action need not always be stated; it can be implied.
Juan había cerrado la ventana antes de salir. (stated)
Juan had closed the window before leaving.
Juan había cerrado la ventana. (implied)
Juan had closed the window.

The preterite is used for completed past actions. There is generally a specific time either stated or implied.
It is used for actions that can be viewed as single events.
Ella caminó por el parque.
She walked through the park.
Ellos llegaron a las ocho.
They arrived at eight o'clock.
It is used for actions that were repeated a specific number of times, or occurred during a specific period of time.
Ayer escribí tres cartas.
Yesterday I wrote three letters.
Vivimos allí por cuatro años.
We lived there for four years.
It is used for actions that were part of a chain of events.
Ella se levantó, se vistió, y salió de la casa.
She got up, dressed, and left the house.
It is used to state the beginning or the end of an action.
Empezó a nevar a las ocho de la mañana.
It began to snow at eight in the morning.

The imperfect is used for ongoing past actions, There might be a general time expression, but there is no indication of when it started or when it ended.
It is used for habitual past actions.
Almorzábamos juntos todos los días.
We would lunch together every day.
Las señoras siempre charlaban por las mañanas.
The ladies would always chat in the mornings.
It is used for actions that "set the stage" for another action.
Yo leía cuando entró mi papá.
I was reading when my papa entered. (note that "entered" is preterite)
It is used for telling time and stating one's age.
Eran las siete de la noche.
It was seven o'clock at night.
La niña tenía cinco años.
The little girl was five years old.

The easiest explanation of the difference between the preterite and the imperfect is that they are both past tenses. We tend to record things in the past.
If you were to record the preterite, it would be best done with a snapshot. The action happened in a "flash".
The imperfect, however, went on over a period of time, and would be best recorded on video.
Pretérito perfecto = Past, simple. = Yo comí en McDonalds ayer... The action was finished, ¿when? yesterday... I ate in McDo yesterday.
Pretérito Imperfecto = Past... without a clear end... = Yo comía en McDonalds ayer... (you should add something else, because the sentence is :S weird) cuando llegó Juan.. I was eating at McDo when Juan arrived.
You were doing something in the past, probably is finished now, but in your sentence is not.
Ahora en español la explicación. El pretérito perfecto simple, o pretérito, , indica que la acción ya se acabó, y en la frase lo dejas claro con la conjugación en pasado.
El pretérito imperfecto o Copretérito, muestra una acción en el pasado que no se ha acabado o que no se había acabado.
Pretérito = Past, is just different way of saying that.




PRESENT PROGRESSIVE
http://www.spanishdict.com/topics/show/77

The present progressive tense combines the present indicative of the verb estar (to be) with the present participle of another verb to indicate an action in progress. The present progressive tells what a person "is doing" right now.

Estoy hablando con mi madre. (I am speaking with my mother (right now).)
Los niños están jugando en el patio. (The children are playing in the yard (right now).)
¿Estás yendo a la tienda ahora? (Are you going to the store now?)

Present Progressive Forms

The present progressive is a verb phrase consisting of both estar (the "is" part which indicates the tense) and the present participle (the "-ing" part which indicates what the action is). To form the present progressive, conjugate estar to the present indicative tense and add the present participle form of the verb that the person is actually doing.

Present Progressive Formula: estar + present participle (verb stem + -ando for -ar verbs/-iendo for -er and -ir verbs)

Estoy hablando I am speaking
Estás hablando You are speaking
Está hablando You (formal) are speaking, He/she is speaking
Estamos hablando We are speaking
Están hablando You (all, formal) are speaking, They are speaking

Present Progressive Uses

Single Current Actions

Simply, what a person is doing right now, and action they are currently participating in.

Está escribiendo un ensayo para su clase de español. (He is writing an essay for his Spanish class.)
Estamos cocinando la cena. (We are cooking dinner (right now).)
Están durmiendo en el dormitorio pequeño. (They are sleeping in the small bedroom (right now).)

In English and Spanish, this is usually expressed using the present progressive, but it is possible to use the present tense in Spanish as well.

¿Qué haces? (What are you doing?)
Limpio la cocina. (I'm cleaning the kitchen.)
¿Cómo estás? (How are you doing?)
Estoy bien, gracias. (I´m doing well, thank you.)

Study Spanish.com
http://www.studyspanish.com/lessons/presprog.htm

Remember, only use the present progressive for actions that are "in progress." Compare the uses of the present indicative with the uses of the present progressive.

Estudio español. (Present Indicative)
I study Spanish. I do study Spanish.
*I am studying Spanish (THESE DAYS).

Estoy estudiando español. (Present Progressive)
*I am studying Spanish (RIGHT NOW, AT THIS MOMENT)***

It is important to remember that you would never use the present progressive to say something like "We are going to Spain this summer." Use present progressive only for actions that are "in progress."



++++Fue or Era
the differences between the two simple past tenses of Spanish are fairly easy to grasp: The preterite typically refers to actions that took place at a definite time in the past, while the imperfect tense refers to actions that occurred numerous times and/or didn't have a definite end.
However, for the foreigner, applying those concepts to the past tenses of ser can be problematic, partly because it seems in practice that native speakers commonly use the imperfect of ser (that's era in the third-person singular) for states of being that had a definite end, while an application of the rule above might suggest use of the preterite (fue in the third-person singular).
The following email exchange indicates some of the challenges in dealing with the past tenses of ser. Both sides of the written conversation have been edited for clarity, brevity and the purposes of this article.
Question: The difference between preterite and imperfect is not too hard to grasp for most verbs. As an English speaker, we certainly understand the difference between "I slept" and "I was sleeping" or "I slept at home" and "When I was in college, I would sleep at home on the weekends." But, when we want to use the past tense of "to be," it is hard to understand when to use the preterite or the imperfect, because in English we seldom say "was being" (you could say, "he was being foolish," but you wouldn't say "It was being 8 p.m.), and we never say, "used to was" or "would was." The most difficult part of figuring out the fue/era issue is in questions like the following:
¿Cómo fue tu clase? Or ¿Cómo era tu clase?
¿Cómo fue tu juventud? Or ¿Cómo era tu juventud?
¿Cómo fue su reinado? Or ¿Cómo era su reinado?
I'm pretty sure that all of these sentences can be said, but I'm sure that they have different meanings. I'm not sure how to think about the real difference in meaning between fue and era because I don't think we have this distinction in English, even a contextual difference.
Any help with a method of thinking specifically about the differences between fue and era would be greatly appreciated.
Answer: Yeah, they can be confusing. Here's a lesson I wrote some time ago, but I'm not sure how well it answers your specific question: Which Past Tense of Ser or Estar?
All of your questions would probably work best with fue. In a way, they're all talking about an event, for which the preterite typically is better. If we were talking about inherent characteristics, era would typically be better. So we might ask, ¿Cómo era tu profesor? because then we'd be talking about inherent characteristics (unless, perhaps, if the intent of the question was to ask whether the teacher had a bad day). I'll have to think about this a bit more — the distinction isn't always clear.
Question: Yes, that lesson helps but I'm still confused. I have had some native speakers tell me that the questions I posed could all be asked with either fue or era but that the following ways were the preferable ones for each sentence:
¿Cómo fue tu clase?
¿Cómo era tu juventud?
¿Cómo era su reinado? (if you want a description of what happened during his reign), or
¿Cómo fue su reinado (if you want an answer like, it was quite tyrannical)
I have a hard time making a distinction between an event and a characteristic. I read a story about a man whose daughter died. He was talking about her and said, "Esa chica, señor, era mi hija." I could think of that as an event. It might be a long event but still I can imagine a lifetime being referred to as an event. I also would think that his daughter's death was a terminating action so, for both reasons I would have used fue.
One thing that might help would be if I could see some questions in which the following answers would be best used:
Fue bastante malo, or
Era bastante malo.
If I saw a list of many questions that required the answer with fue and another list that required the answer with era, I might be able to find the commonality among the list and then discern the difference in meaning of fue and era.
Now that I think of it, the same problem exists with estuvo and estaba with questions. ... Anyway, the fue/era conflict is more important because I seem to have to make that decision much more frequently than the estuvo/estaba decision.
If you could give me some examples of when fue malo would be best used and era malo would be best used, that might help a lot.
The first thing I'd say is that if a reasonably knowledgeable native speaker says that some word usage sounds better, you're probably better off most of the time taking that person's word over mine — there's something to be said for learning a language from birth. That's one reason I often advise students to ask questions in our forum — there are some regular participants there who are native speakers, and they sometimes can offer a perspective that even the most knowledgeable foreigner cannot.
When I research to answer a question, in addition to consulting various reference works and thinking about what I've heard used in real life, often I perform various web searches to get an idea if sentence constructions are used often enough to make their way to the Web. In the case of your original three sample sentences, era was overwhelmingly the choice in the similar sentences I found. That's not an infallible test by any means — but it does show that era was a reasonable choice.
I've thought about this some more, and because I've been unable to find any reference works to go into the matter of era vs. fue in any detail, I've tried to come up with a grammar rule of my own. Part of the problem is that there seem to be some situations where both forms of ser are used, and there doesn't seem to be much difference in meaning. To use your last example, I've easily found examples of "era mi hija" and "fue mi hija," although the former seems to be more common. (Under the circumstances, I'd probably use era as well, as my daughter will always be my daughter, no matter what.)
Also, in real life it appears that constructions such as "era feliz" and "fue feliz" are both quite common. The former is sometimes applied to temporary situations, and the latter sometimes to entire lifetimes. So I'm not convinced that native speakers necessarily make a clear distinction in all situations.
That said, mostly as an experiment, I did a quick Web search to see how "era malo" and "fue malo" were most commonly used. Here are the top Google results (simplified here, and with duplicates omitted) for each word, first for era:
¿Einstein era malo en matemáticas? (Was Einstein bad in mathematics?)
Si ayer era malo ... (If yesterday was bad ...)
¿Quien dijo que la marihuana era malo? (Who said marijuana was bad?)
Ricky Martin pensaba que ser gay era malo. (Ricky Martin used to think being gay was bad.)
¿Era malo Hitler en realidad? (Was Hitler actually bad?)
And for fue:
El semestre pasado fue malo. (The past semester was bad.)
Tu amor fue malo. (Your love was bad.)
El paisaje de amenazas digitales fue malo durante el año pasado. (The cyberthreat scene was bad during the past year.)
Google Wave fue "malo" mientras duró. Google Wave was "bad" while it lasted.
Al final "Chiquidrácula" no fue malo para Panamá. (In the end "Chiquidrácula" wasn't bad for Panama.)
Granted, this is a very small sample. But it seems to me that the distinction, indistinct though it may be, between inherent characteristic (era) and event (fue) makes some sense with these examples. Not perfect sense, though — even in the context of the original, it would have been possible to say "si ayer fue malo."
I wish I could come up with a clearer rule, but I'm not sure it's possible. Nevertheless, I hope you've found this exercise useful.