---Tina, _______ ----G-R-E-E-N. A. what's your first name? B. what's that in English? C. spell "green", please.
The rubbish _____ is produced every day is becoming a serious problem in cities around the world.
More and more trees were cut down. _____, many animals are dying out.
We should often keep _____ touch with each other, because we are good friends.
—Do you think a radio is useful in learning English? —Sure. A radio can _____ listening English songs and reports.
—Do you know _____? —Sorry, I don’t know.