应该是must talk 还是must be talk 请说详细点.谢谢

应该是must talk 还是must be talk 请说详细点.谢谢 must 是must to do还是must doing 还是must do? must doing还是must to do? we must stop ------(talk)when class begin you must be something to talk you must talk to her in english The knots of your package must be tied tightly.应该是of还是on? It must be Jim.的反义疑问句?It must be Jim,______?怎么填?应该是isn't it 还是isn't he?说明原因,please.. must be哪个是词是动词?must还是 be? must do sth 还是 must to do sth 是must be to do还是must be doing I must go now 还是 I must going now 是must not be 还是must be not must的否定回答是need 还是用must you must not talk in the class改为祈使句. we must stop talking同义句：we ()talk any more phones must be kept off _____ the talk