---IsthatmaninaredT-shirtMr.Smith,yourmathteacher?   --...

問題詳情：

--- Is that man in a red T-shirt Mr. Smith, your math teacher?

    --- It _______ be Mr. Smith. He has gone back to America.

    A. must      B. can          C. shouldn’t     D. can’t

【回答】

D

知識點：情態動詞

題型：選擇題