They talked about it for hours, ________ they decided not to go.

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We are going bike ________ in the country.

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London is full of ________ in summer.

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He's the boy who can ________ very fluent English.

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－What are you doing for the summer vacation?

－We're going ________ on the Great Wall.

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We need a new TV set and has ________ the model.

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We don't allow the children to sit up ________.

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Tom didn't pass the exam and was ________.

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I mean you eat ________ food.

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We must keep ________ of nature.

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