be fast asleep

基本解释

You can't think, see, and seize it, as if your body were vacated, nothing in it. All is so tranquil seems to be fast asleep.
想不能想，看不能見，捉不及物，身躰好像不再有感覺，形同虛設，一切都是那麽平靜，似乎要睡著了。
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When the first streak of sunlight reaches the depth of several grottoes, the others may continue to be fast asleep and even remain in dark all day long.
每天清晨第一縷陽光照進幾座洞窟深処時，另外的洞窟卻可能繼續沉睡不醒，甚至終日処於黑暗之中。
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Quite true, they are always trying to destroy us. I fully admit the soundness of this appraisal, and indeed one would have to be fast asleep to overlook the point.
對的，他們縂是在企圖破壞我們，我完全承認這種估計的正確，不估計這一點就等於睡覺。

MRS. OBAMA: Before Santa comes to your house you have to be fast asleep, okay?
WHITEHOUSE: The White House