Pollution is a serious problem. Scientists have _______ some good ways to save it.

You have more apples than ______ . But mine are better than _______.

Sorry, Mr Green. I have_______my homework at home.—Never mind. But don’t forger next time.

Tom used to be afraid of snakes. — ________. I thought they were scary.

Did you go to Sam’s weekend party? —– No, I ______________.