The population problem may be ______ one of the world today.
--- What did the policeman say to you, Liu Ying?--- He told me ______ my purse in the bicycle basket. It’s too dangerous.
I _______ in London, but now I live in New Yorker.
—I think classical music is pleasant.—_______ I think it’s boring.
Michael is fond of _______, but I prefer _______.
There is a lot of traffic on the road now. You ________ play football there!