A. have answered B. answered C. will answer D. has answered
A. will have sold B. has sold C. will sell D. sell
A. had made B. have made C. are making D. is making
A. They have been B. It is C. It was D. It have been
A. taught B. have taught C. had taught D. teaches
A. it would take B. had it taken C. it takes D. it had taken
A. had forgotten B. was forgetting C. has forgotten D. forgot
A. had been waiting B. were waiting C. have waited D. has waited
A. have told B. had told C. had been telling D. tells
A. had already rang B. has already rang C. had already rung D. rang
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