How to form the passato prossimo?

Passato prossimo is a past tense that describes an action that has happened and is now over, i.e. a complete action. Example : il mercoledi sono andata a scuola - on Wed I went to school (happened once and is now over)

Formation: Avere + past participle OR Essere + past participle NB must be present form of essere or avere.

Past participles: -are verb: -ato -ire verb: -ito -ere verb: -uto

but with some irregularities that you just have to learn.

Those verbs that take essere, the past participle agrees with who is doing the action where the avere verbs never do.