请将He must lock his car改成现在完成时如题,请不要乱回答.

请将He must lock his car改成现在完成时如题,请不要乱回答. All the afternoon he worked in his study with the door .　　A.to lock B.locking C.locked D.lock he spent all the morning ——in his study A.locking B.locked C.to lock D.lock 这里为什么选B? He can't find his key.He ---------- them.A.must lost B.must have been lost C.must have lost please make sure youPlease make sure you _________ the door before leaving the room.A.lock B.will lock C.should lock D.must lock选什么？为什么？ c#lock 与 lock 区别 his h() hurts. so he must stay in bed. the child has a bad c() he must __(finish)his homework first. he must change his dietchange changes? Our teacher must be in his office,A mustn't he B can't he C isn't he D must 请帮忙翻译：Lock pressure must be 100bar or more below the unlock pressure. 请从语法角度加以说明~（1）39.the medicine ________cool,clean and dry.A.must keep B.must be kept C.must be carried D.must be in49.________ his stamps he has collected are from Canada .A.two hundreds B.hundred of C.two hundred of D.two hund He must be in his room now ,_____?A.mustn't B.isn't he请注明原因,3Q Lock it 请告知, _____ by his accent,he must be from Southwest China.(A) Judged(B) Judging并请说明理由 He _____from his seat and said that something must be done to ____people’s living standards.A.rose;raise B.rose;rise C.raised;raise D.raise;rise 这个选哪个?为什么?知道的请告诉我一声 His bike is broken.He walk to school.A.must B.have to C.has to D.has His bike is broken.So he-------walk to schoola must b may c can d has to