French language Q&A Forum

How could I say "I can go a day without you" (for example) using the same "se passer de"? I know we can say "Je peux me passer de toi pendant un jour" but could I eliminate the "pendant" and say something along the lines of "Je peux me passer de toi un jour" or "Je peux me passer un jour de toi" (but here you have to split them)?
If not, what would be the correct way to say it? Maybe "pendant" still has to be there in cases such as these?

Why are only "a qui" and "a laquelle" accepted as answers, while "dont" isn't?

I think I'm a bit confused when to use "voir" and "regarder". Also, would it be wrong to say "elle s'assoit toujour près de la fenêtre"? 

What is the common french word for someone who is a  "tattletale", specifically a child.  I have seen the verb "dénouncer" in my lessons but not the noun.  What would be used in a primary school where there are always children who "tattletale"? Dénounceur/euse?    Merci!