a door must be either shut or open

a door must be either shut or open 6.There is someone knocking at the door,who _____ it be?A.can B.may C.must D.need 21页7.Listen ,there is a knock ------the door .It must be TomA.on B.to C.in 理由 who is knocking at the door?i suppose------must be bob.A.the one B.it C.who D.he 反意疑问句,关于must的(3句)情态动词must在句子里出现的时候,反意疑问句应该怎么写(横线处填)1.must+be+被动语态,例如The door must be opened,_________?2.must+be+名词,例如He must be a teacher,_________?3.must+动 Who______ it be that is knocking at the door?—It ______ be Father,but I’m not sure.A.can; must B.can; may C.must; can D.may; must -Who ＿＿it be that is knocking at the door -It＿＿b-Who ＿＿it be that is knocking at the door -It＿＿be Father ,but I'm not sure .A.can ;must B.can ;may C.must ;can D.may ;must 这题选什么?为什么?老师又公布答案了：选A！但 —Who______ it be that is knocking at the door?—I—Who______ it be that is knocking at the door?—It ______ be Father,but I’m not sure.A.can; must B.can; may 　C.must; can 　D.may; must -What is behind the door? -There must be a dog sitting behind it. sitting behind it,为什么是sitting?而不是sit 或sat? Someone is knocking at the door.It be Tom because he Shanghai already.A.must; has left B.can't;has left There is someone ringing the door bell.Who _____ it be?A) can B) must C) may D) will为什么不能是 D the door is closed and the lights are off.he_______ be at home.A.must B.can't C.can D.mustn't 鱼和熊掌不可兼得 英语a door must be either shut or openyou cannot sell the ______ and drink the milk must be a kind girl i think you must be a teacher是什么意思must be为什么不是must are?must I can't find Yao Fang.He must be ( ) the door.填介词 1.----Who is knocking at the door 1.----Who is knocking at the door ,mary?-----It ( )Susan A must be B may be 2.nothing serious.You caught ( )cold .A a bit B abit of C little 3.Though some of the suits in the shop are nice .But they ( ) too much A co —There is somebady at the door.Who _____ it be?—It ______ be Mr.Huang ,the driver.I asked him to come and get me this time.A.may;must notB.will;may C.can;must notD.could; must