This machine ________ I have been looking after for 20 years, is still working perfectly.

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He paid the boy $ 10 for washing ten windows , most of ________ hadn’t been cleaned for at least one year.

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The hotel ________ we stayed was both cheap and comfortable.

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The student ________ will win the English competition will be sent to England for further study.

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Look , there is a house on the ________ of the forest.

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If the river is heavily polluted, fish in it will be in ________ of dying out.

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The price has been increased ________ 5 dollars.

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The scientists are still working ________ inventing new methods of reaching outer space.

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When the fire broke out, people ________ to the exit.

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It didn’t take them long ________ their houses after the fire.

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