Chen Lin, who teachesEnglish?—— Mrs. White. She has lived in China for years.Chinese is very good.

What are you going to do this weekend? —I _____ yet.

The invention of spaceships makes ________ human beings to travel to the moon.

Look, Mr Green is on the other side of the street. — It _____ be him.He has gone to London on business.

Attention, please. Sorry to tell you the flight has to be ______because of the heavy snow.