_______ Alice and Bob? They are my classmates.
My way to work out the problem is the same ____Jack’s but different____Mary’s.
----How terrible the air is! Yes,if there are ___trees, there will be ___air pollution in our city.
—Will you buy the white watch or the red one ? ----I’ll take_____.One is for my mother and the other is for my sister.
—What is he going to ______ when he ______ up? —He’s going to be a doctor.
I had _____useful umbrella when it rained.