_____ Chinese pianist Lang Lang becomes the first Chinese to be named International Artist of the Year.—Yes. This is _____historic moment for him.

All of us must do_______ to help protect the environment，or we will have more hazy weather雾霾天气.

This is Tom.____ is a teacher.

l transplants are no longer sciencefiction imagination ,”a surgeon has said,____that they are ___possiblebut technically complex..

candles only, we need ________ candle.