—Shall we go out for a walk?—Sorry, I can’t. I _____ my homework.A. do B. was doing C. am doing
_______ he is young, ______ he knows much.
______ he is in trouble, his best friend always helps me.
The plane was late, _________ we has to wait for half an hour.
Tony never spends money on traveling____ he likes staying at home.
________ is not an easy thing for everyone to master a foreign language. A. That B. This C. It