I am ________ all day's study; I'm considering ________ to the cinema tonight.

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I have the honor to ________ to have dinner with them.

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The professor has received the letter ________ to give a lecture in Princeton Institute.

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________ I used to go skating. I'm interested in fishing now.

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A poem written by an American poet is usually harder to understand than ________ by a Chinese poet.

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I could hardly believer it, but ________.

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At the ________ of the gun, Mr. Smith rushed out of his office.

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It is suggested that a doctor ________ immediately.

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—Come in, Peter. I want to show you something.

—Oh, how nice of you! I ________ you ________ to bring me a gift.

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A．never think, are going

B．never thought, were going

C．didn't think, were going

D．hadn't thought, were going

—Will somebody go and get Dr. Wang?

—He's already been ________.

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