---May I go out to play with my friends now, Dad?---No. You ______ let your mother know first.A. may B. need C. must
There was a _____ rain yesterday evening. It rained ________.
There is _____ river at the foot of the mountain(山). _____ river is dangerous.
--- _________are you late for school? ---Never.
—______ English can you speak?—Only a little.
March is _____ month of the year.