“Why did they hold the meeting?”“ ________ new officers. ”

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He then explained ________ it was all about .

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________ a long way to the town, so ________ a long way to go yet before we arrive at our destination.

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________ poet and ________ play-writer is to attend the meeting this evening.

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Could we go in and visit this house? Yes, you ________ .

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Such problems ________ air pollution and heavy traffic are becoming more and more serious in every big city.

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________ is known to the world, Mark Twain is a great American writer.

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—Do you remember ________ he came?

—Yes, I do. He came by car.

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You may express your idea ________ writing.

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It was so cold that they kept the fire ________ all night.

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