_____ private cars are bringing us convenience, they may also cause more traffic accidents and pollution.
A．While B．As C．If D．Since
_____ all over the hills and around the lake are wild flowers of different colors.
A. Grow B. To grow C. Growing D. Grown
—It’ll take at least 2 hours to do this !
—Oh , ! I could do it in 30 minutes .
A. come on B. pardon me C. you are right D. don’t mention it
Elephants have their own way to tell the shape of an object and it is rough or smooth .
A. 不填 B. whether C. how D. what
—Sorry to you , but could I ask a quick question ?
—No problem .
A. worry B. prevent C. trouble D. disappoint
More than a dozen students in that school ______ abroad to study medicine last year.
A. sent B. were sent C. had sent D. had been sent
