We use the imperfect tense when talking about actions that took place in the past and didn’t have a definite beginning and end. That means that an action took place during a non-specific amount of time or was repeated an indefinite number of times.
She used to cook. (imperfect) She cooked yesterday. (preterite)
The first sentence states that she cooks, but we don’t know when, or for how long. In the second sentence we know when she cooked – yesterday. (an specific period of time)
Let’s see another example:
She used to come late. (imperfect) She came late 3 times (preterite)
The first sentence states that she came late, but we don’t how many times. (indefinite number of times). In the second sentence we know how many times she got late, 3 (specific number of times).
Situations that we need to use imperfect:
• · Habitual actions (Sofia used to eat chocolates.)
• · Descriptions (Franz’s car was blue.)
• · Past progressive actions (Fernando was studying when I got home.)
• · Feelings/mental actions (I loved him; I thought he was wonderful.)
• · Intentions (I was going to go to class, but…)
• · The time it was/how old you were (I was nine when I went to Disney)
• · Había—the past tense of “hay” (There were fifty people at the party.)
Generally, as soon as we introduce a definite time phrase into the sentence (yesterday, last week, five years ago, three times, etc.), that means we have to use the preterite tense. The exception to that would be things like “había” or talking about intentions—things that, by their nature, are states rather than actions—in the past, they will always be imperfect. Phrases that are not definite (often, sometimes, every once in a while, again and again, etc.) mean we should use the imperfect.
FORMING THE IMPERFECT
Drop the –ar and add:
Drop the –er/ir and add:
Let’s take a look at some examples:
I used to eat a lot when I was a child. Yo comía mucho cuando era niña.
I used to live in California. Vivía en California.
We would enjoy our vacations. Disfrutabamos durante nuestros vacaciones.
IRREGULAR VERBS IN THE IMPERFECT
There are only 3 irregular verbs in the imperfect tense: ser (to be), ir (to go), and ver (to see/to watch).
Ella era su novia. She was his girlfriend.
Renzo iba a fiestas. Renzo used to go to parties.
Ella veía televisión japonesa. She used to watch japanese tv.