1.--- Where is Mary?--- She ____ in the library. A. should be B. must be C. can be D. must have been2.His room is dark. He must ____ to bed. A. go B. be going C. have gone D. have been gone3.“Will your father stay home tonight?”“I’m not sure, He ____to work.” A. must go B. can go C. may be gone D. may be going4.“Where is Tom?”“He isn’t here I think he ____ have gone home.” A. may B. must C. might D. A or B or C5.“I think Helen is at home.”“ No, she ____ be at home, for she phoned me from the airport just five minutes ago.” A. mustn’t B. needn’t C. can’t D. daren’t6.He’s late. What ____ have happened to him? A. can B. may C. should D, must7.“ _____ he be watching TV now?”“Yes, he _____ be watching TV now.”“ No, he _____ be watching TV now.” A. Must; can; mustn’t B. Can; must; can’t C. Must; must; can’t D. Can; can; mustn’t8.“____. He have left yesterday?”“Yes, he ____ yesterday.”“No, he ____ yesterday.” A. Must; must have left; can’t have left B. Can; can have left; can’t have left C. Can; must have left; can’t have left D. May; must have left; shouldn’t have left9.You must be a writer, ____ you?A. mustn’t B. areC. must D. aren’t10.You must have seen her yesterday, ____ you?A. mustn’t B. haven’tC. didn’t D. don’t