어언 + time span + -이/가 되다/흐르다
before one knows it, already (time passing)
Example
한국에 온 지 어언 십 년이 되었어요.
Before I knew it, it's been ten years since I came to Korea.
Word parts
어 at, in+언 thus, here
Built from two classical function syllables; used for time slipping by unnoticed.
Good to know
Almost always with a span of time: 어언 30년 'a good thirty years already'.