________ that? That's our teacher, Mr Li.

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The man downstairs found ________ difficult to get to sleep.

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Could you tell me ________ train is leaving for Shanghai?

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Lucy and Lily are ________ good at Chinese because they have been here for years.

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Li Lei has three sisters. One is a doctor, ________ is a driver. The third is a teacher.

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The man you saw just now was an old friend of ________ .

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Each of us ________ to Beijing more than three times.

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________ is difficult in the world if you put your heart into it.

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There are many tall trees on ________ sides of the road.

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This problem is so difficult that ________ students can work it out.

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