Every means ________ tried since then .

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They each ________ an English story book.

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He is the very thief that the police ________ .

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Either the shop assistants or the manager in the shop ________ kind to the customers .

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All ________ except Xiao Wang .

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It is generally believed that teaching is _______ it is a science.

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In the office I never seem to have time until after 5∶30 p.m. ________many people have got home.

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Unless ________ to speak, you should remain silent at the conference.

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_______ wonderful?

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Not until all the fish died in the river ________ how serious the pollution was.

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