The population of India has _____ quickly, because they don’t have a Family Planning policy like China. [ ]

sthe headmaster, Tony. You______hello to him.－Sorry.I didn’t notice him.

Bob used to ______difficulties in studies, but now he does well in all subjects.

__________ drive so fast, you’ll run the risk of losing your license for six months.

Don’t _____ so often. It’s bad for your health.—I have to. But I know I should have enough sleep.