V-자 (connecteur temporel)
as soon as, when suddenly
Form
Verbal root + -자 + the following sentence — “as soon as / when”… ».
Function
Links two events that are very close together: the second occurs at the exact moment the first takes place.
Why this form?
-자마자 — « "as soon as / the moment that": emphasizes even more explicitly the absence of a time gap and is very common in spoken language; the -자 The "connective" approach is more narrative in nature and can describe the reaction that occurs at that moment.
-(으)니 — « "While doing / when…, I notice that…": often used to introduce an observation or a discovered consequence ; -자 emphasizes the immediate sequence of the two events.
Register and nuance
This -자 is a narrative connective. It is not the sentence-final hortative -자 “let’s…” analyzed later.
Forms not to confuse
-자마자
문을 열자마자 전화가 울렸어요. — As soon as I opened the door, the phone rang.
-(으)니
밖에 나가니 비가 오고 있었어요. — When I went outside, I found that it was raining.
Examples
내가 갑자기 나타나자 그는 깜짝 놀란다. — As soon as I suddenly appear, he jumps in surprise.
문을 열자 차가운 바람이 들어왔다. — As soon as I opened the door, cold air came in.