Mr Smith is the very doctor for you ________.

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The water isn't fit ________.

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This small country is known ________ rich in natural resources.

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When I came in, I saw her ________ in the sofa, deep in thought.

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________, the children went to the park.

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I would appreciate ________ back this afternoon.

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Did ________ on time make her teacher angry?

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Before ________ , we must check the machines.

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That was so serious a matter that I had no choice but ________ the police.

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________ a teacher in a university, it is necessary to have at least a master's degree.

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