How do you form the imperfect tense in Spanish?

The imperfect tense is used in Spanish to describe something in the past or to talk about something that happened often or habitually, for example going to school every day.

It has two different types of endings, one for AR verbs and one for IR and ER verbs.

The AR endings are as follows:

Yo -aba

Tu -abas

Él/ella - aba

Nosotros - ábamos

Vosotros - abais 

Ellos/ellas - aban

To add this to the verb you take the AR off the infinitive of the verb to leave you with the stem for the imperfect tense that you can then place the endings on! e.g. hablAR (infinitive) --> habl (imperfect stem) --> yo hablABA (imperfect yo form)

The ER/IR endings are both the same and are as follows:

Yo -ía

Tu -ías

Él/ella - ía

Nosotros - íamos

Vosotros -íais

Ellos/as - ían 

To add this to the verb you take the ER off the infinitive of the verb to leave you with the stem for the imperfect tense that you can then place the endings on! e.g. comER (infinitive) --> com (imperfect stem) --> yo comÍA (imperfect yo form)

To add this to the verb you take the IR off the infinitive of the verb to leave you with the stem for the imperfect tense that you can then place the endings on! e.g. vivIR (infinitive) --> viv (imperfect stem) --> yo vivÍA (imperfect yo form)