0 past simple and past participle of happen
1 (of a situation or an event) to have existence or come into existence:
No one knows exactly what happened but several people have been hurt.
I don't want to think about what might have happened if he'd been driving any faster.
I don't know what I'd do if anything happened to him (= if he was hurt, became ill, or died).
What happened to your jacket? There's a big rip in the sleeve.
What's happened to my pen? (= Where is it?) I put it down there a few moments ago.
2 to do or be by chance:
[ + to infinitive ] They happened to look (= looked by chance) in the right place almost immediately.
[ + (that) ] Fortunately it happened (that) there was no one in the house at the time of the explosion.
[ + that ] It just so happens that I have her phone number right here.
She happens to like cleaning (= she likes cleaning, although that is surprising).
I happen to think he's right (= I do think so, although you do not).
As it happened (= although it was not planned), I had a few minutes to spare.
It is frightening to think what might happen if she left him.
I could tell from her expression that something serious had happened.
The police showed him a photo to try to jog his memory about what had happened on the night of the robbery.
"Do you remember much about the accident?" "No, it all happened so suddenly."
On Sundays I just wear any old thing that I happen to find lying around.
Did she happen to mention whether she would be coming?
I just happened to be walking past when he came out of the shop.