These days they were up at the crack of dawn.

这些天他们在破晓时就起床。

《柯林斯英汉双解大词典》

At the crack of dawn, he would run up the slopes with his skis on, an unbelievably backbreaking activity.

在黎明时分，他会穿着滑雪板跑上斜坡。做这样一项非常耗费体力的运动让人难以置信。

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The rooster in your backyard wakes you up every morning at the crack of dawn.

每天黎明时分后院的公鸡会叫醒你。

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And we do. Cracking jokes,grins, Long past the crack of dawn Like"How long will you be up?"

VOA: special.2009.04.17

At the crack of dawn, the dreaded wakeup call destroys any hope of a leisurely sleep-in.

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The working day began at 8am, the crack of dawn for investment bankers in those days.

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We arrive at the crack of dawn, having been told that the runners will be training early.

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