I found ________ impossible for ________ to work out the maths problem.

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The news that they failed their driving test discouraged him, ________?

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Someone is ringing the doorbell. Go and see ________.

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I like your watch. Can you lend ________ to me?

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I don't think ________ is any need for a guide on our journey.

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________ is a fact that English is being accepted as an international language.

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I hate ________ when people talk with their mouths full.

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________ used to be thought that the earth was square.

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________ is know to everybody, the moon travels round the earth once every month.

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Is ________ necessary to take off our shoes when we enter the lab?

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