He kept on        until midnight though he was tired.

Thanks for        us English so well.

There        a banana and three apples on the desk.

—Let’s       . —OK.

—The more I get to know Nancy, the more I can realize that we have a lot        .
—No wonder she is your best friend.

It is up        you         where to go.

Why not         your teacher for help when you can’t finish         it by yourself?

—I usually go there by train.
—Why not        by boat?

You can do a lot of things on holiday, such as        .

I happen         the answer to your question.