Why should trees ________ on the mountains ?

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The river smells terrible. People must ________ dirty things into it.

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The woman ________ blue is Li Hua's mother.

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The water must be ________ too hot ________ too cold.

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Neither you nor she ________ hard at English.

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He ________ the flowers and trees in our school.

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You'd better speak English ________ after class.

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We ________ an English book.

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Are you sure he doesn't ________ if I use his bike?

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“________ will the shirt be ready?”

“In about 3 days.”

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