So we must be careful when we use the Internet.

The weather of these days is really bad.It’s foggy and there is haze in the air.So,we can’t see the things very far.Every morning,when I pull back the curtain,I only can see the building dozens miles away.When I go to school,I must be very carefu So we must be careful when we use the Internet. We have a little time l____,so we must hurry up ,or we will be late. OK,so we must be on time .Can we bring music players to school? So We must Study hard Something unusual seems ____,so we must be more careful,(happen) We must ___(be) careful. We must be strict_____ourselves_____our work. We must be happy,however we We must be must be这句话意思 SO DO I,YOU MUST BE HAPPY --we must start for the work now. ---so must we 为什么这里的回答用so must we 而不用so we must We used to be so we can be so perfect We must be careful.怎么改祈使句 We must be careful_____(cross) the road. We must be quiet in the library. We must be l------- to the school