After Yang Liwei succeeded in circling the earth, ________ our astronauts desire to do is walk in space.

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American women usually identify their best friend as someone ________ they can talk frequently.

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The disc. digitally ________ in the studio, sounded fantastic at the party that night.

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The flowers ________ sweet in the botanic garden attract the visitors to the beauty of nature.

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The flu is believed ________ by viruses that like to reproduce in the cells inside the human nose and throat.

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Bill's aim is to inform the viewers that cigarette advertising on TV is illegal, ________?

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The number of deaths from heart disease will be reduced greatly if people ________ to eat more fruit and vegetables.

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The first use of atomic weapons was in 1945, and their power ________ increased enormously ever since.

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Children under 12 years of age in that country ________ be under adult supervision when in a public library.

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I can't say ________ when he will come back.

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