The door remains ________.

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Why not try _______ the back door if they can't hear you on the front door?

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Once_______, it will never be forgotten.

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The days _______ the Chinese women were looked down upon are gone forever.

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Can you tell me why ________ took them such a long time to control the birth rate?

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You can do _______ you like at home.

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Some agree with Jim, but _______us _______ with Sam.

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Questions of this kind ________difficult ________.

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I kept him ________for about an hour.

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They eat ________ the fingers of their right hands.

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