hard for him to fit in a new class, in which______ he was familiar with

What does your friend Carl do after school—He ___________chess in a club. He’s a good player.

I have to go now. My parents want me _______ back home by ten o’clock.

We are living in an age _______ many things can be done on computers and the Internet.

is not for us to finish the work in a day.