1. El Pretérito vs. El Imperfecto
A question of HOW LONG?

2. Let’s REMEMBER…. Preterit tells us when something is DONE.
It’s essentially the –ed tense.
Imperfect tells us that something used to happen, or happened for some time in the past, but we don’t know for how long… it may even still be going on.
The key words are USED TO and
WAS …-ING.

3. The Preterit is a COMPLETED past action that is DONE! * POOF! *
The Imperfect is an ONGOING past action that we don’t know for how long it has happened, or if it is still going on?!?

4. Use the PRETERIT in sentences that have indicated a SPECIFIC time, like one day, last Saturday, July 4th, etc.
Last night I ate chicken soup.
Anoche comí sopa de pollo.
On Saturday I went to the hockey game.
El sábado fui al partido del hockey.

5. Here is the list of key words that indicate SPECIFIC TIME, PRETERIT… put them in your notes!
Anoche last night
Ayer yesterday
El martes (lunes, etc.) on Tuesday
El 5 de octubre (any date) October 5th
El año pasado last year
El mes pasado last month
La semana pasada last week
El fin de semana the weekend

6. I ate shrimp from time to time. Comía gambas de vez en cuando.
Use the IMPERFECT in sentences that you don’t know for how long the action occurred. A GENERAL time like always, on Saturdays, sometimes, etc.
I ate shrimp from time to time.
Comía gambas de vez en cuando.
I used to study all the time.
Estudiaba todo el tiempo.

7. Here is the list of key words that indicate a GENERAL TIME… IMPERFECT…put them in your notes!
Siempre always
A veces sometimes
De vez en cuando from time to time
Los sábados (martes, etc.) on Saturdays
Todo el tiempo all the time
Cada día (lunes, mes, etc.) every day
Generalmente generally
Frecuentemente frequently

8. SO… In SUMMARY:
Preterit means –ED, and is POOF done! It is a completed past action.
Imperfect means USED TO, and WAS –ING! We don’t know for HOW LONG it happened in the past…. It may still be going on. WHO KNOWS? Only the speaker.

9. Try this. Would you choose preterit or imperfect for the following sentences?
I went to the store yesterday.
a. preterit b. imperfect
I saw Adela there.
She was wearing a gray t-shirt.
She and her friend were buying toothpaste.
I bought a new CD.
You must get them all right. The last correct answer will allow you to move on!

10. ¡ Sí !
It’s preterit because there is a specific time indicated and you know that it is POOF, done! 
¡Buen trabajo! Back

11. No… mira otra vez
There must be a specific time indicated. That’s why you choose preterit! It could also be that it’s just DONE…POOF!
Back

12. ¡Buenísimo! A general time, or no indication
of how long the action occurred
is the IMPERFECT tense! Yeah!!!
Back

13. Uh-oh… piensa un poco…
There must NOT be a specific time indicated. That’s why you choose imperfect.
Go back and read the sentence and ask yourself… “For how long has this action occurred? Could it still be going?”
If you cannot answer those questions… it’s IMPERFECT!
back

14. You’re doing ¡FANTÁSTICO!
Now… lets try it in Spanish!
Choose A or B to fill in the blank.
El año pasado mi madre _______ un
carro nuevo.
a. compró b. compraba

15.  ¡Buen Trabajo!  She bought it… that’s a completed past action.
Plus we know the specific time…
last year.

16. ¡Ay! No… sigue tratando. Is there a specific time? USE PRETERIT!
Is there a general time? USE IMPERFECT!

17. Try one more: _________ libros de misterio todo el tiempo.
a. Leí b. Leía

18. ¡MUY BIEN! I used to read… all of the time.
All the time is a general time indicating imperfect!
Bien hecho.

19. ¡Ay! No… sigue tratando. Is there a specific time? USE PRETERIT!
Is there a general time? USE IMPERFECT!

20. ¡Ay! No… sigue tratando. Is there a specific time? USE PRETERIT!
Is there a general time? USE IMPERFECT!

21. Let’s try a couple more…
Anoche ___________ la televisión por dos horas.
a. miré b. miraba
El sábado pasado yo ___________ al centro comercial.
a. fui b. iba

22. Increíble… Last night I watched television for two hours.
LAST NIGHT is the specific time that tells you to use preterit!
¡¡¡Buen trabajo!!!

23. ¡Tú eres la BOMBA!
Last Saturday I went to the mall… POOF, it’s done… I went on the specific time of last Saturday… which indiactes preterit.
¡Muy bien!

24. Alright… let’s see what ya got?
Now pick the correct form of the verb, AND the reason WHY! Yikes! Think clearly! Look for the key words!
Siempre ____________ a la escuela.
a. conducía/ I drove
b. conduje/ siempre is a key word for the
preterit tense
c. conducía/ siempre is a key word for the imperfect tense
d. conduje/ I poof drove, that one time

25. Bzzzttt… incorrect!
Wrong tense, wrong reason…
Do you know why?

26. Right tense…
Wrong reason…
Mira otra vez…

27. FANTÁSTICO Muy bien… YOU GOT IT!
Siempre IS a general time and we now know that means… IMPERFECT! 
Keep up the good work and clear thinking!