We've planted ________ trees in the center of our city this year.

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My father has got eight ________ stamps from all over the world.

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Can you help me with the housework?

________.I'm busy preparing for my examinations.

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The ________ population may be the greatest challenge of the world today.

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I wasn't sure if he ________ at the meeting .

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You have sports for an hour after school every day, ________?

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The twins are ________ tall ________ strong.

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The students are all busy ________ the exams.

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________ of people coming to China for a visit is rising.

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I' m afraid that she can't come to help you today. You' ll have to turn to ________.

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