The boy has recognized clearly where is the duty ________.

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There is ________ sugar in this drink and that one is ________ salty.

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While you are at work or taking a walk, your body ________ two calories an hour.

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You'd better go to see the doctor and have a blood ________ . You look so pale.

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The middle-aged woman is too fat so her private doctor advises her ________.

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The Chinese diet ________ much sugar or fat so it ________ the healthiest in the world.

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They eat less sugar and that's ________ they have ________ white teeth.

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She is weak in body and she has walked a long distance. Now he is ________ tired.

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I need one more stamp before my collection ________.

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________ troubles me is _______ I can't learn all these English idioms by heart.

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