The perfect tense is used to describe an action or event that occurred in the past. For example, you would use the perfect tense to express the phrase "I played football yesterday"
The perfect tense is constructed with the subject (I, you, she...) followed by an auxiliary verb and then a past participle.
The majority of French verbs take avoir as the past participle. There is a group of 14 verbs that take être as the auxiliary verb, as well as all reflexive verbs (such as se laver).
Constructing the past participle:
For verbs that end in -er take off the er and add é. For example the past participle of jouer is joué.
For verbs that end in -ir take off the ir and add i. For example the past participle of finir is fini.
For verbs that end in -re take off the re and add u. For example the past participle of vendre is vendu.
The auxiliary verb is used in the present tense so for verbs that take avoir the forms are:
These forms are then followed by the relevant past participle.
For example I played football would be translated as J'ai joué au foot.
Il a fini ses devoirs
Ils ont mangé beaucoup de gâteau