French and English. The prominence of English makes it easier for those who don't speak French, but harder for those who want to learn it. In some countries and cities, you know, if you don't communicate in their language, you won't survive, but in Paris, you do survive speaking only English, which can be unfortunate when you are trying to learn a new language!
France uses the euro (abbreviated €). One U.S. dollar is about 0.86 Euros.
Between two and three euros. Sometimes it costs more than a coffee.
At my university, we have Les Crous, and I know other universities have it as well. It is amazing because it's a cafeteria where you get a whole lunch with dessert and fruit for only €3.30. I went there two days last week, and it was pretty good. My favorite was the day they gave us chicken, rice and broccoli. I love broccoli, and these plates remind me of back home, where the meals feel complete and healthy.
