While building a tunnel through the mountain,________.

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A．an underground lake was discovered

B．there was an underground lake discovered

C．a lake was discovered underground

D．the workers discovered an underground lake

—What do you suppose made her worried?

—________ a gold ring.

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This sentence needs ________.

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—Who told you about Dad’s illness?

—The doctor in ________.

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He ________ out to break the world record. He ________ a good example to all the players.

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I insist that a doctor ________ immediately.

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In summer, the temperature sometimes ________ as high as 39%.

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I’ve worked with children before, so I know what ________ in my new job.

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How about the two of us ________ a walk down the garden?

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I can hardly imagine Peter ________ across the Atlantic Ocean in five days.

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