—–I think the man over there must be Tom.—–It _____ be him. He has ______ to America.
I failed in the exam. But my mother ___ me to try again.
____ wonderful news report he wrote!
–I’m sorry I ___ my exercise book at home just now. --Don’t forget_____ it to school tomorrow, please.
I think everybody should ______ to protect wild animals.
If I don’t buy them, _____ will buy them.