Forming the imperfect tense

There are three steps to form the imperfect tense of all verbs:

1. Take the nous form of the present tense, eg: for avoir → nous avons
2. Then drop the nous and the -ons from the end, so that we are left with the stem, eg: av
3. Finally choose the appropriate subject pronoun (ie the person you are talking about) and add the imperfect endings from the table below:

Here's another example – we want to say "I was watching/I used to watch TV" (regarder = to watch):

1. Take the nous part of the present tense of regarder → nous regardons
2. Remove the ons and remove nous → regard (the stem)
3. Choose a subject pronoun, eg: je regard and add the correct ending from the table below to the stem, eg: je regard + ais → je regardais la télévision