-Who’s that man riding along the street. Is it Tom?-It ______ be Tom. I saw him in the library just now.
The teacher said that they ______ hard-working students.
---Do you like talking with your friends on the telephone or on the QQ? --- _______. I enjoy chatting face to face.
The teacher encourages her students _____ English as much as possible.
I will stay at home and read books if it _______ tomorrow.
She _______ a lot of money on clothes.