—Yang yan, are you coming with us?
—I’d love to, but something unexpected ______.

The manager was concerned to hear that two of his trusted workers _____.

My watch _____ at nine o’clock, but now it _____.

--- what do you think of store shopping in the future?
---- Personally, I think it will exist along with home shopping but___________.

I ___________ to phone her all day, but whenver I phone her, the line is engaged.

－Why didn’t you give me a call last night?
－Well, I couldn’t. My phone _____________.

A good film producer must make sure that his films ____ fit into the needs of the changing market．

Hurry up! Flight 4406      off at 18:40.

—What’s that noise, John?
—Oh, don’t you know that the school library      ?

Traffic conditions in Beijing ________ for decades. At first people only complained about jams during rush hours，but today every hour is rush hour.