His mother had thought it would he good for him to _________ from home and earn some money on his own.

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Are you going to ________ the challenge of lasting a whole week without arguing!

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The government is calling on the several paper mills to ________ immediate action to stop pollution.

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It seems that he hasn't realized the important part he is ________ in the matter.

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I can't afford a lawyer so I shall have to ________ myself.

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The teacher ________ with a brush what he had written on the board.

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Better care should be ________ of the earth.

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－What is the ________ of studying after the exam?

－We're not studying for exams.

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The best way to solve the problem is to use the knowledge and technology that some countries have already ________.

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If we work together and ________ what we know, we'll be building a better future for all of us.

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