Years ago we didn't know this, but recent science ________ that people who don't sleep well soon get ill.

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She can't help _____________ the house because she's busy making a cake.

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——You should have thanked her before you left.

——I meant_______, but when I was leaving I couldn't find her anywhere.

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I've worked with children before, so I know what _________ in my new job.

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There are five pairs _________, but I'm at a loss which to buy.

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My chief purpose is ________ the difficulties of the matter.

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“Bill, keep the things ___________ here secret, will you ?”said the manager after the meeting.

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She will have to move somewhere else, for she can't _______ the loud noise any longer.

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Great Britain __________ England, Scotland and Wales.

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We should protect the trees from ____________.

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