1.how do you like the review
2.you're very kind to help me
3.it's hard for us to learn a second language
4.it's not easy to climb some mountains
5.fish must live with water
6.I'm busy with something interesting
7.it's not safe for us to feed animals
8.why are you looking at yourself in the mirror
9.it's necessary for us to get to school on time
10.you should speak English a lot