as put forward______ most challenging question for us to answer.—Yes, it really is. I have never heard______ harder one.

Excuse me. Is the supermarket far from here—No, it’s about ___________.

17．The movie is to deucate people about environmental problems ______our planet.

May I smoke here—— If you____, that’s the smokingsection over there.

mous athletes and entertainerssuchhigh salaries—Well, at least I think scientists should be paid more．