My sister met him at the street yesterday afternoon, so he __________ your lecture.

─ Look, Stella is there!─ That ______ be her. She doesn’t like singing.

Within a few years China ____ well have the most advanced railway industry in the world.

—The similarities between social networks are striking.—That ________ come as no surprise，because they are all products of the Internet. 

The light is on in Mr. Green’s room. He _______ be at home.