1¡¢Every possible means have been used to prevent the pollution, but the sky is still gray.

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2¡¢My uncle has bought some books, each of them is worth reading.

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3¡¢It is the first time that I came to Beijing.

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4¡¢We meet on the last Friday of every month to talk about poems and poets which we like.

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5¡¢At one point we were so high that we found us cycling through clouds.

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6¡¢I remember that it was in the classroom where I met Jim. He was reading then.

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