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

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European football is played in 80 countries, ________ it the most popular sport in the world.

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The boy wanted to ride his bicycle in the street, but his mother told him ________.

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The missing boys were last heard ________ in the old house.

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She set out soon after dark ________ there an hour later.

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The first text books ________ for teaching English as a foreign language came out in the 16th century.

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“Can't you read?”Mary said ________ to the notice.

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________ is a good form of exercise for both young and old.

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I would appreciate ________ back this afternoon.

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－I usually go there by train.

－Why not ________ by boat for a change?

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