Please excuse me, sir, ________ early. I have to collect my 6-year-old daughter from school in half an hour.

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It's hard to believe that some old textbooks published ten or twenty years ago ________ in our university today.

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That boy ________ his own bike by knocking down a bicycle ________ at the roadside.

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Young as he is, David has gained ________ rich experience in ________ society.

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I ________ to get there before 5 o'clock, but now the rain is pouring down. They ________ for me impatiently.

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A．promised; must be waiting

B．have promised; ought to wait

C．promise; may have waited

D．will promise; could wait

—Do you think he will do me the favor?

—As far as I know, he's the last one to help others. He ________be prepared to give you a hand, though.

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________ he stayed at the seaside and wrote his new book.

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As is known to all, ________ attention you pay to your spelling, ________ mistakes you are likely to make.

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You can hardly imagine ________ great difficulty the woman had ________ her children.

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I had no idea which was the better choice, so I took ________ of them.

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