On my way to school ,I saw a watch ________ on the ground.

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We are all ________in the _____ story.

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The soil in the forests ________ the dead leaves of the trees above.

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Tom studied late into the night ,________the entrance examination.

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________cleaning the room ,we had a rest.

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Helen said she wouldn't finish her homework exercises until ________.

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He crossed the street ,________at left and right .

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________the story ,we couldn’t help laughing.

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Are you interested in ________ English or ________ English?

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I didn't know when ________.

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