—Must I take part in the activity?
—No, you _______. You’re too young. You should look after yourself.
A. mustn’t B. can’t C. don’t have to
Running every day ______ good for my health.
A. is B. areC. am
Last month, I _______ the high jump in our school sports meet.
A. took part in B. joinedC. join
Sam spends two hours _______ his homework every day.
A. to do B. doing C. do
—Would you mind ______ here?
—I’m sorry. I won’t do it again.
A. not smoking B. not smoke C. not to smoke