They need enough time ________ by themselves.

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We find it hard ________ on well with him.

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Slaves (奴隶) fought ________ their freedom.

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They are ________ their new classmate.

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It's very cold outside today. You need ________ warm clothes.

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Children don't have enough time ________ football.

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Don't argue ________ your brother. He is young.

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The old man is ________ to shout at the dog.

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You ________ ask your parents for some help when you are in trouble.

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--- Must I clean the blackboard now?

--- No, you ________.

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