Do the boys in your class enjoy playing chess?—______ likes it, but many of them like football.

David watches TV six hours a day and eats much junk food, but he never exercises. So he is ___.

Look at the boy running on the playground. Is it David? —It ______ be him. I saw him go to the teachers’ office just now.

This is the book _______ I have read these years.

.—_____my dog?—-It’s under the chair.