Is the man standing outside the teacher’s office Mr. Zhou? –No, it ______ be him. He has gone to Hong Kong for an academic conference.

Would you mind closing the window to stop the wind _______ the papers away.

My son wants a pet dog for long, but I have no time to buy _____for him.

Cathy, are you going to buy a flat in Shanghai? —You must be joking. I can’t __________ one there.

When will the World Exposition (世博会) begin? —The Expo will beginMay 1, 2010.[ ]