There can be no life on the earth without water. —-That’s right. Water _____ everywhere.

_____do you sleep every night? —Six to eight hours.[ ]

When I came in, I found Lucyby the windowto music.

It’ll be ten years ___ we have the chance of seeing each other.

What do you think of this math problem?—It’s too easy. _____ in our class can work it out.