The teacher isn't waiting for us.We won't go to Beijing by train
Is the teacher waiting for us?shall we go to Beijing by train?
She can't do her homework by lunch time,
can she do her homework by lunch time?
We shouldn't obey the rules of the school.
should we obey the rules of the school?
You never play baketball after class.
Do you always play baketball after class?
I can't go home at nine every day
Must I go home at nine every day?