The teacher told me to write an ________ composition.

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I don't think ________ necessary to tell him about it right now.

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I am not sure ________ it's a good idea.

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I was watching TV ________ the light went out.

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Don't play jokes ________ others.

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Are you interested ________ Bill Gates?

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He spends much time ________ workers.

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My brother likes ________ basketball.

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________ elephant is ________ useful animal.

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I'll ask him when he ________.

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