Hi Yair, 1. honestly I don't think there is any significant difference between the two words but let's wait for others' comments... 2. there is a definite difference according the size of the space. Since we are talking about rooms vs halls (which is pretty self explanatory) I would rather say they have similarities because both of them have the same function to lead you through a smaller space to a bigger one. So you can have an "előszoba" in a flat or house while you can find "előcsarnok" in a museum for example. 3. "egyetért" means that someone agrees with an opinion "megegyezik" means when two or more people come to an agreement (so they work it out together) 4. "most" means right now "most már" sounds like if you have waited for something to finally happen I'm a bit unsure right now (most) whether I succesfully explained it or not, but hopefully it's more undestandable already (most már) :)