--Who’s singing in the next room? Is it Lucy?---It       be her. She has gone to New York.

Now that the sign reads, “No person ______ smoke here”, please choose a seat in the smoking area over there if you _______ smoke.

— Must I feed the goldfish now? — No, you ______. But you must do it before supper.

--The research on the new bird flu virus vaccine is challenging and demanding. Who do you think can do the job?--________ my students have a try?

 - Can your uncle speak English? -_______. But he can speak Chinese.