1. --- Must we clean the classroom now?
--- No, you needn't. It after school.
A. may clean B. must clean
C. need be cleaned D. can be cleaned
2. We can eat in the cafe. But we eat in the classroom.
A. can B. didn't C. can't D. aren't
3. We be careful when we walk across the road. There're too many cars now.
A. can B. may C. must D. could
