The Perfect Tense is a Past Tense. It is used to talk about actions that took place in the past and are completely finished. (i.e: I ate a pizza; I have done my homework).
In French, the Perfect Tense is called "le Passé Composé". It is a compound tense, made of two parts. The first part is the Auxiliary and the second part is the Past Participle.
1. The Auxiliary
To form the first part of the Perfect Tense, you need to use the correct auxiliary (AVOIR or ÊTRE) and conjugate it in the Present Tense. The majority of verbs use AVOIR as an Auxiliary.
2. The Past Participle
To form the second part of the Perfect Tense, you need to use the Past Participle of the main verb. For regular verbs, the past participle is formed by replacing the infinitive endings with the past participle endings as follow:
-J'ai regardé un film. (I watched a film/ I have watched a film)
-Elle a fini son sandwich. (She finished her sandwich/ She has finished her sandwich)
-Nous avons attendu pendant une heure. (We waited for an hour/ We have waited for an hour)
Note: You must make sure both parts are written!
Je regardé DOES NOT MEAN I watched and is COMPLETELY INCORRECT!
Be careful! To write these sentences in the negative form: ne...pas must be around the Auxiliary.
-Je n'ai pas regardé de film.
-Elle n'a pas fini son sandwich.
-Nous n'avons pas attendu pendant une heure.