Group 1 (verbs ending in -er):
* Singular: -ais, -ais, -ait
* Plural: -ions, -iez, -aient
Example: *J'avais mangé* (I had eaten)
Group 2 (verbs ending in -ir):
* Singular: -issais, -issais, -issait
* Plural: -issions, -issiez, -issaient
Example: *Tu avais fini* (You had finished)
Group 3 (irregular verbs):
* Singular: -ais, -ais, -ait
* Plural: -ions, -iez, -aient
Example: *Il avait vu* (He had seen)
Important Notes:
* The auxiliary verb "avoir" is conjugated in the imparfait tense (avais, avais, avait, etc.)
* The past participle of the main verb remains unchanged.
* The plus-que-parfait is used to express an action that happened before another past action.
Example sentences:
* J'avais fini mon travail avant de partir. (I had finished my work before leaving.)
* Elle avait déjà mangé quand je suis arrivé. (She had already eaten when I arrived.)
* Nous avions vu ce film plusieurs fois. (We had seen that movie several times.)
Let me know if you have any other questions!