For everyone's safety, we _________ a1ways remember the law against driving after drinking.    

He said he _____ swim when he was six.          

用could, can, may, must, needn't填空。
1.  A: _______you answer the question in English?
    B:  Sorry, I_______._______I answer it in English.
    A: No, you _______.You _______answer it in Chinese.
2. A: _______I ask a question?
    B: Yes, you________.  But you _______wait a minute.
3. A: _______I use your eraser, Bill?
    B: Sorry.  I don't have one.  Ask Mary.  She _______ have one.
4.  A: _______you help me do the shopping?
    B: OK. Sure.
5.  A: _______you sweep the floor?
    B: But_______  finish my homework first.
    A: OK.  You_______ do it at once.

—can you go swimming with us this afternoon?
—Sorry, I can't.  I______ do the chores at home.

—______ you find your math book?
—Yes, I can. 

—Mum, must I finish my homework right now?
—Oh, you_____.

Four hundred dollars for a pair of shoes, you __________ be joking!

I _____ find my English book. Where is it? Do you know?       

—Mike! You _____ play with the knife. You might be hurt.
—OK, Mom.