The Great Wall winds its way from west to east, ________ deserts, mountains, ________ valleys, till at last it reaches the sea.

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To ________ east of the city lie a mountain, south of which is the village where I was born.

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For centuries the upper class in Britain spoke French ________ the common people spoke English.

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The British Isles is a group of islands that lie ________ the west coast of Europe.

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As ________ unemployment is very high nowadays, it's very difficult for people to find ________ work.

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________, I lost heart in English learning, but my teacher often said to me, “Keep on working hard, and you'll succeed ________.”

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It's generally believed that teaching is ________ it is a science.

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The world is ________ sever continents and four oceans.

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As a result of destroying the forests, a large ________ of desert ________ covered the land.

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Students should be encouraged to finish their homework ________.

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