---I met your boss in the street this morning.---Ah? You _____ be joking. He flew to Europe yesterday!
—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.
—Jim, remember to return this book by Friday. — .
The book won’t until the end of the year.