I *almost* V-ed: 을 뻔했다

V + 을 뻔했다 is used to show that something almost or nearly happened, usually as an unintended or unexpected result. Note that this is not to be confused with 거의:

직행 비행기를 타면 론돈에서 서울까지 거의 11시간 걸려요.
If you fly direct, it takes almost (practically, mostly, as good as) 11 hours to fly from London to Seoul.

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늦잠을 자서 오늘 아침에 버스를 놓칠 뻔했어요.
I almost missed the bus this morning because I overslept.

모자를 잃어버릴 뻔했어요.
I almost forgot my hat!

자전거로 언덕을 내려가고 있을 때 너무 빨라서 넘어질 뻔했어요.
When I was going down the hill on my bike, I was travelling so fast that I almost fell off.

작년에 교통 사고로 죽을 뻔했어요.
Last year I almost died in a traffic accident.

졸업식을 위해 양복을 입은 친구들을 못 알아볼 뻔했어요.
When I saw my students wearing suits I almost didn’t recognise them.

한국어 배우는 걸 그만둘 뻔했어요.
I almost gave up learning Korean.

지난 번에 남자친구와 말싸움을 했을 때 헤어질 뻔했어요.
The last time I had an argument with my boyfriend we almost split up.