A. fell behind B. may fall behind C. should fall behind D. would fall behind
A. signed B. had signed C. would have signed D. should sign
A. will arrive B. would arrive C. could arrive D. should have arrived
A. didn't see B. hadn't seen C. haven't seen D. wouldn't see
A. had better not do B. would rather not do C. oughtn't to do D. shouldn't have done
A. be infected; be sent B. was infected; be sent C. should be infected; was sent D. be infected; was sent
A. Should face B. might face C. could have faced D. must have faced
A. would tell B. had told C. told D. would have told
A. What is required B. What requires C. It is required D. It requires
A. had followed B. follow C. would followed D. have followed
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