This is your morning wake-up call.

这是你早上的闹铃。

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For example, you could request a wake-up call in the morning.

比如你想要早晨的叫醒服务。

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Even as Adam Riess was regaling the media with an amusing, self-depreciating, anecdote about his early morning wake-up call from Oslo, deep in the bowels of UCL's Department of Physics and Astronomy researchers were putting the finishing touches to a camera that could finally shed some light on the discovery that won him the Nobel Prize for Physics.

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Initially, I took baby steps toward the early morning wake-up call.

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It was 4 o'clock in the morning and my wake-up call was in two hours.

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