Directions: Beneath each of the following sentences there are four choices marked A, B, C and D. Choose the one answer that best completes the sentence.
21. ---- When shall we begin our meeting tomorrow?
---- You ______ come. We’ve changed our plan.
A. can’t B. shouldn’t C. needn’t D. mustn’t
22. Do you think ______ a struggle to learn English well in high school?
A. that B. this C. it D. which
23. He is much better now, but he hasn’t completely ______ his operation(手术).
A. devoted to B. recovered from C. used to D. suffered from
24. Amy regretted ______ the weight-loss pills which caused her liver ______.
A. taking; to fail B. taking; failing C. to take; failing D. to take; to fail
