Why don't you prepare it before hand?

怎不早做准备?

《现代汉英综合大词典》

How clever of you to book the ticket before hand!

你真聪明,预先把票子买好了.

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Inspection and acceptance before hand over to the clients.

风力发电机组移交用户前的验收检验.

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Make a check on your answers before hand in.

交上来之前再核对一下答案.

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Note: If you want to travel separately, please notice the work staff before hand.

注: 若有单独行动, 请提前通知工作人员并说明原因.

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