It is pretty well understood ________ controls the flow of carbon dioxide in and out the atmosphere today.

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It's no use answering ________ he asks.

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________ to take the magazines out of the reading room?

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If time ________, I'll go and see you.

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It's the first time the painting ________ to the public.

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The house ________ was damaged in the fire has now been repaired.

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The school ________ Mr. Smith teaches is a world-famous one, ________ was set up 100 years ago.

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How I wish I ________ to the museum with you yesterday!

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Don't play any longer. It's high time you ________ down to your study.

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We need a new manager ________ the business ________.

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