We have discussed the formation of the perfect participle already in the first part of the French Survival Guide. For regular verbs, we have the following summary. It is to be separated between verbs ending in -er , -ir, -re or -oir. The stem is to be found when taking the ending away.
Formation of particip passé with regular verbs
verbs ending in -er
verbs ending in - ir
verbs ending in -oir
verbs ending in -re
Stem + é
Stem + i
Stem + u
Stem + u
manger => mangé
finir => fini
vouloir => voulu
battre => battu
eat => eaten
end => ended
want => wanted
beat => beaten
parler => parlé
choisir => choisi
voir => vu
conclure => conclu
speak => spoken
choose => chosen
see => seen
finish => finished
fumer => fumé
dormir => dormi
recevoir => reçu
smoke => smoked
sleep => slept
receive => received
penser => pensé
sentir => senti
apercevoir => aperçu
think => thought
feel => felt
notice => noticed
Zahlreiche und vor allem wichtige Verben, bilden das Partizip Perfekt aber nicht nach diesem Muster, sondern sind unregelmäßig, das heißt, man muss sie einzeln lernen. Es macht Sinn, sich diese Verben einzuprägen.
Formation of particip passé with regular verbs 
