Preterite & Imperfect

Question

What is the difference between the preterite and the imperfect? Both are the past tense, so how do I know when to use each one?

Answer 1

Both the preterite and the imperfect are in fact past tenses but they are each used in unique instances.

The preterite is used in very specific instances and is a tense that is heavily favored when referring to events in the past that are seen as "completed". Below are a list of situations in which you can reference when determining whether or not to use the preterite.

1. Dated/Completed Actions - I went to the store and I bought eggs.
2. Used to narrate a series of events - We went to the store, bought the eggs, stopped for gas, then went home.
3. Used to mark the beginning or end of an event - It started to rain.
4. Age one turned - Last November, I turned 29.

I like to describe the imperfect as the story telling tense. If I can describe a past experience of mine in such a way that will cause the listener to be able to visualize and place themselves in that moment, I'm likely using the imperfect. Some uses would be:

1. Habitual actions - I used to go camping every summer with my family. (Used to...)
2. Ongoing actions with no specific start or end - We were swimming. (-ing)
3. Events in progress - I was eating my ice cream while my sister was talking on the phone. (Something was happening)
4. Physical and emotional states - He was very nice and excited to learn.
5. Telling time - It was 3 o'clock.
6. Background information like weather and temperature - It was sunny and hot that day.