you must be careful when you ___ with fireworksplay .为什么?我选的是 playing.那为什么要用原形.不可以用 played

you must be careful you must be careful改为祈使句 You must always be careful with it . You must be _(careful) than before. you must be careful.为什么说careful没有be不能形成谓语,不是有must吗 填空题 When you walk___the road,you must be careful. you must be careful when you （ ）the street You must be more _____next time.是careful 还是carefully You must be careful with your pronunciation.改为祈使句 you must be careful with your pornunciation.改为祈使句 You must be careful when crossing the street.改为祈使句 while___(cross)the street,you must be careful It is dangerous .You _____(must be)careful You must be careful to c_the road.It's dangerous. You must ___(be) careful (在红绿灯处） You must be careful to c___ the street. We must ___(be) careful. 同义句转换 No matter what you do,you must be careful.=Whatever you do,you ______ _____be careful.