Could I sleep on it and let you know tomorrow?

能不能让我晚上考虑考虑，明天答复你？

《牛津词典》

I need more time to sleep on it. It's a big decision and I want to make the right one.

我需要更多的时间再考虑一下。这是个重大的决定，我想做出正确的决定。

《柯林斯英汉双解大词典》

Think, blink or sleep on it?

思考、眨眼还是在上面睡觉？

youdao

You can sleep on it.If you still feel like going in the morning, - I'll take you to the airport.- No. I want to drive.

VOA: standard.other

And if not, sleep on it, think about it for a while and then keep going.

如果实在写不出来，就睡一觉，第二天再决定。仔细想一想后继续写。

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It says they should be placed on a separate sleep surface from their parents,without blankets, pillows or other soft bedding.

VOA: special.2009.08.26

The farmer asks for an evening to sleep on it, and when the prospector returns the next day, he politely declines.

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It was nighttime by that point, so decided to sleep on it and wait until morning to really try them on.

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The U.S. executives, unsurprisingly, tended to make decisions on the spot, while the Swiss liked to sleep on it overnight and then regroup.

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