Imperfect - Preterite
Tue, 07/01/2008 - 7:50pm — Doc Molly
Hope you enjoyed this podcast. Thanks to Dan and Tavo for getting the topic started. And maybe we'll hear from them again soon. 
In studying the imperfect and the preterite I discovered that much of the time, either one can be used. Often the difference just leads to a subtle change in meaning which really doesn't matter that much. So when it's not obvious which to use, don't worry to much. You're probably okay either way.
When I am trying to figure out which to use, It helps me to ask this question: "Am I describing the scene (imperfect) or am I speaking of an isolated event or specified period during which something occurred (preterite)?" Hope that helps. Please leave your questions and comments here.
 | A New Reference Grammar of Modern Spanish author: John Butt,Carmen Benjamin asin: 0071440496 |
Imperfect vs Past Progressive
When I am describing something that happened in the past past while something else was going on, do I use the past progressive or the imperfect?
For example:
I was swiming when it begain to rain.
Nadaba cuando comenzó a llover.
Estaba nadando cuando comenzó a llover.
Gracias por la ayuda.
Imperfect vs Continuous Imperfect
Okay, I researched the answer in my favorite Grammar Reference book: A New Reference Grammar of Modern Spanish. See link above.
The use of either one is okay, but the use of the Coninuous Imperfect (Past Progressive) is preferred when the action that was in progress occurred over a discrete period of time in the past. So in the above example I would say:
Estaba nadando cuando comenzó a llover.
However, there are certain verbs with which the continuous is not commonly used: estar, poder, haber, ir, venir, regresar, volver, andar.
Therefore, if you wanted to say, "I was returning from the store when you arrived."
Volvía del super cuando llegaste. - o - Regresaba del super cuando llegaste. - o - Venía del super cuando llegaste.
Also when talking about background occurences, the imperfect is commonly used. For example, if you wanted to say, "The cats were sleeping, the birds were singing and the air smelled of flowers, when I arrived at my grandpa's house."
Los gatos dormían, los pájaros cantaban, y el aire olía a flores cuando llegué a casa de mi abuelo.
I hope that helps. It sure helped me to look it up.