French language Q&A Forum

The passive voice in several examples where we needed "was sent" and "had prepared" used plus que parfait ie) était envoyé and avait préparé, but for "the students were welcomed", my use of étaient accueillis was incorrect and the correct answer was the p.c.: Les étudiants ont été accueillis was correct. This seems illogical to me. Please explain the difference.

This was the question: 

From a drop-down multiple choice, I answered that it meant "I have everything" but I wasn't sure that was correct because of the "les"

The correct answer was, "I have all of them," but couldn't that be written as, "J'en ai tous?" That's where I got confused.

Si je changeais maintenant here you have used imparfait can I use passé composé here

For Indiana Jones lived through extraordinary adventures 

I used "a vécu par" for "lived through".  Is this incorrect?

Can anyone refer me to the lesson as to why "je me suis brossé les dents"   brossé has no extra e and the speaker is a woman. Has to do with "les dents" being the direct object, I think, but would love to read the lesson.

Can you also use ‘je ne pouvais pas dormir’ - if not why please..

Thanks 

Liz

What word would we use in a more formal, or written context?