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いつの間にか, 何時の間にか, いつのまにか
1. before one knows, before one becomes aware of, unnoticed, unawares
不知不觉间,在察觉之前,悄然无声,浑然不觉
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眠る, 睡る, ねむる, ねぶる
1. to sleep
2. to die, to rest (in peace), to lie (buried), to sleep (in the grave)
3. to lie idle (e.g. of resources), to lie unused, to lie untapped, to lie untouched
4. to close one's eyes
入睡