いつの間(ま)にかSuddenly, Unnoticed, Without noticing, Too soon

Structure

いつのまにか + Phrase

Details

About いつの間にか

Although a combination of いつ 'when', の, 間(ま) 'interval', に, and か; いつの間(ま)にか is a set expression that is used as a stand-alone adverb to mean 'suddenly', or 'without noticing'. Literally, it just highlights an unknown interval within which something occurred, as seen by the question marking particle, か.

Fun-fact

Coming mainly from the inclusion か, this grammar pattern often carries the nuance of surprise. When you want to convey the same feeling without the nuance of surprise, あっという間(ま)に may be used instead. This is a similar expression which literally means 'in the time it takes to say あっ'.

楽(たの)しいことをしているとあっという間(ま)に時間(じかん)が過(す)ぎるよね。

Time flies when you're having fun, doesn't it?

Synonyms

Examples

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オレはみんなからいつの間(ま)にかポチと呼(よ)ばれるようになった。

Without noticing they have come to call me 'Pochi.'

いつの間(ま)にかもう1年(ねん)が経(た)ってしまった。

Without me realizing it, another year has passed (all too soon).

「いつの間(ま)にか彼女(かのじょ)はネイティブみたいに話(はな)せるようになった。」

'Without me realizing, her speaking has grown to that of a native.'

帽子(ぼうし)を被(かぶ)ってないといつの間(ま)にか風邪(かぜ)を引(ひ)く。だからきちんと帽子(ぼうし)を被(かぶ)って。

If you do not wear a hat, you will catch a cold before you know it. That's why you should put on a hat.

あなたの子供(こども)から目(め)を離(はな)せばいつの間(ま)にか迷子(まいご)になるかもしれない。ご注意(ちゅうい)ください。

If you take your eyes off of your child, they might get lost without you even noticing. Please be careful.

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いつの間にか – Grammar Discussion

Most Recent Replies (6 in total)

SevenZeven
```
しばらく入院していて、久しぶりに外に出ると、**いつの間にか**冬になっていたと見つけた。
```
I couldn’t remember this construction at all, so I tried 「知らずに」 as a blind shot in the dark. Does the sentence make any sense like that?
wrt7MameLZE33wlmpCAV
I think you would be understood saying 知らず. いつの間にか seems to fit the sentence just a little better because of the nuance of surprise. In my opinion, it’d be fair for there to be a hint that 知らず is not what’s expected because that seems like a good guess to me.
Fuga
Hey @SevenZeven !

As @wrt7MameLZE33wlmpCAV said, you probably would be understood, but 知らずに here sounds extremely unnatural. 知らないうちに is a lot more natural. However, 知らないうちに and いつの間にか has a difference in nuance.

知らないうちに has a nuance that you had some control, or was aware about what was happening, but not entirely sure how or why it happened. いつの間にか has the nuance that something happened without warning because you were not paying attention to it or you couldn’t pay attention to it (due to an external or internal force). いつのまにか has the nuance of ‘it happened in a blink of an eye’, but 知らないうちに does not.

Example:

オレはみんなからいつのまにかポチと呼ばれるようになった。
Without noticing they have come to call me “Pochi.”
Nuance: I just started to notice that people are calling me ‘Pochi’. Because I wasn’t paying attention to what people were calling me, it seems to...