Tom fell off the tree and hurt himself. We should________ a doctor at once.

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Tom fell off the tree and hurt himself. We should________ a doctor at once.

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If you can't come, ________ and let me know.

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从所给的四个选项中选择最佳答案

He is badly ill. We must ________ a doctor at once.

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A．send for　　　　　　 　B．send to

C．send away　　　　　　 D．send up

On the highway, buses or cars are not allowed to the passengers.

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