conjugation rules and endings for the first group verbs.
Concentrer is conjugated the same way that verbs that end in :
-er. First group verbs always end with
-er as their infinitive. Endings of first group verbs are regular.
Note : Although endings are perfectly regular, spelling changes occur in the stems of verbs in
-cer,
-ger,
-yer,
-eter,
-eler,
-é-consonne(s)-er,
-e-consonne-er, verb
envoyer and similar verbs.
Concentrer verb is conjugated in female form and in reflexive form. Be careful, the past participle of compound tenses must agree with the subject.
Concentrer is conjugated in interro-negative form. The interro-negative form being obtained by inversion of the subject, the placement of the negative adverb follow the same rules as in negative form, giving the following rules:
- in interro-negative form, the adverb
« ne » is always placed first if the subject is a pronoun.
- in simple tenses, the adverbs (
« ne ...pas »,
« ne...plus »,
« ne...jamais », etc...) surround the verb
concentrer and the inverted subject pronoun.
- in compound tenses or in ive voice, the negative adverbs surround the auxiliary and the inverted subject pronoun.
For sound reasons, like in interrogative form, an euphonious
« t » is added to the pronoun of the third person:
« il »,
« elle »,
« on »,
« ils »,
« elles » except when the verb ends with
« t » or
« d »:
« ne concentre-t-elle pas ">« n'aura-t-elle pas concentré ? ».
Always in interro-negative form, and always for sound reasons, an accent appears in first person present indicative tense when the verb ends with
« e ». An euphonious
« e » is replaced by
« é »:
« ne concentré-je pas ? ».
Finally, the interrogative form does not exist in subjunctive and imperative.