——May I smoke here?
——If you , choose a seat in the smoking section.
A. should B. could C . must D. may
Thank you for helping me. I the final exam without your timely help.
A. have failed B. will fail C. would have failed D. must have failed
——Has Tom finished his report so far?
——I have no idea. He it this morning.
A. did B. has done C. was doing D. had done
______ I admit that all these problems are difficult, I don’t agree that they can’t be solved.
A. Unless B. While C. Until D. Since
Clothing made of man-made fibers has certain advantages over _______ made of natural fibers like cotton, wool or silk.
A. the ones B. one C. that D. what
Believe it or not, I am sure that is _______ people call the sixth sense.
A. what B. that C. which D. how