People do not know the value of health ________ they lose it.

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I don't always make such ________ in math.

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She has ________ her elderly parents for many years.

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If you do so, it will ________ a great difference.

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I have the same trouble ________ you.

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________ I had read the paragraph several times, I still couldn't understand it.

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After class all the students take an active part in all kinds of ________ on the playground.

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You are so big and the jar is so small that it could ________ hold one of your feet.

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－________ do you visit the Summer Palace?

－Once a month.

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________ times do you go to the park in a week?

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