や・
The instant one thing happens, the next follows. It is written Japanese: in conversation it sounds like reading aloud.
The moment the train arrived at the station, the waiting passengers all boarded at once.
The moment the curtain rose, the audience fell completely silent.
How to form it
Verb in the dictionary form + や否や
着く → 着くや否や. Always the dictionary form, though the story is in the past: there is no 着いたや否や. 否 negates nothing: the train did arrive.
Shorter and stiffer
Verb in the dictionary form + や
上がる → 上がるや, with the same meaning. This や follows a verb; the や of a list joins nouns.
- Before it
- Something over in a moment: 着く, 鳴る, 開ける, 終わる. In news, often an announcement: 発表される, 伝わる.
- After it
- What happened right then, often how other people reacted. Never a request or a plan.
- Where you'll meet it
- Novels, essays, newspapers.
In use
As soon as she opened the envelope, her expression changed.
The moment the price rise was announced, shoppers flooded the stores to stock up.
As soon as the news broke, share prices plunged.
や alone, as a newspaper would put it.
や否や or なり?
No sooner had the company president taken his seat than he pointed out a flaw in the documents.
Written. The point is the timing: seated, and at once.
As soon as the company president took his seat, he pointed out a flaw in the documents.
The point is how abrupt he was: no greeting first, straight to the fault. People say this one aloud too.
Close neighbours
が早いかN1
"No sooner … than" in written storytelling. The two halves can be about different people or things. A rarer twin of や否や.
No sooner had the alarm sounded than the passengers ran for the exit all at once.
なりN1
Both halves are about one person, and what they do next is abrupt. Heard in speech as well as read.
The moment the child had his shoes off, he dashed upstairs.
そばからN1
Usually not one event but every time: something is done, and at once it is undone or outrun. Said in conversation too.
I forget new words as fast as I learn them.
たとたん（に）N3
The everyday one. The very moment one thing was done, something else happened, suddenly and not by your choice.
The moment I sat down, the phone rang.
Check yourself
1Which one fits?
ベルが
Choose an answer to see why.
2Which ending fits?
試験が
Choose an answer to see why.
More sentences
The moment the alarm sounded, the workers ran for the emergency exit.
As soon as he entered the room, he took off his wet coat.
As soon as the company president stepped onto the stage, every eye in the hall turned toward it.
The moment the cage door opened, the bird flew into the sky.