Guess, how much does it cost? —I think it costs15 and 20 dollars. [ ]

What do you want to be when you ___________?—I want to be a pilot.

It will ______us several years to learn a foreign language well.

Have you seen the movie The Giant Tangshan Earthquake? — Yes, it’s well worth _______. It’s _______ moving that I’ve seen it twice.

Your MP4 is quite cheap. Where did you buy ________? I want to buy ________, too.