verb endings when using être in the passé composé

Question

Why not plural i.e. with an 's' when we are talking about 'we'?Nous ________ les cheveux. We brushed our hair(HINT: Conjugate "se brosser" (to brush) in the compound past (Passé Composé))nous sommes brossénous sommes brossés

Accepted Answer

Hi Kevin,
You might find my response to Leah deals with this point -
https://french.kwiziq.com/questions/view/agreement-of-reflexive-verbs
 
Let me know if you are still confused, hope it helps!

Answer

Hi Kevin, this would probably vie with the question ‘why c’est un, not il est un ?’ for the most asked question here !

The first link is to one previous response. In short, the direct object of ‘ se brosser’ is “les cheveux” which follows the verb, and no agreement applies.

Agreement only applies with the reflexive verb in passé composé when the direct object precedes the verb, as is also the case with verbs conjugated with avoir in compound tenses.

https://french.kwiziq.com/questions/view/why-mark-nous-sommes-brosses-as-almost-correct

https://www.lawlessfrench.com/grammar/agreement-with-pronominal-verbs/