「[何](https://eikaiwa.dmm.com/uknow/questions/44648/)があったの？」と直接その場で尋ねたいときは、これで十分かと思います。お役に立てれば幸いです。
what は「何」、happened は「[起きた](https://eikaiwa.dmm.com/uknow/questions/62416/)」です。
なので、What happened? で「何があったの？」となります。
例：
A: What happened? Are you OK?
何があったの？大丈夫？
B: Oh, don't worry about it.
あ、気にしないで。
>Hey, what did I miss?
This is asking indirectly what happened while you were gone or did not see...
>What happened while I was gone?
This is asking the person/colleague to tell you what happened while you were gone.
Hey, what did I miss?
自分がそこにいなかったもしく見なかったときに何か起きたかを尋ねるときの表現です。
What happened while I was gone?
自分がそこにいなかった時に何か起きたか同僚などに尋ねるときの表現です。
When you want to get some information about what is happening, you can use the following questions:
"What's going on?"
"What did I miss?"
"What's the commotion about? "Commotion" means lots of excitement
なにが起きているかについて情報がほしいとき、このような質問をすることができます。
- "What's going on?"
- "What did I miss?"
- "What's the commotion about?"
commotionはたくさんの興奮のことです。
To miss something = to fail to be present for something, or to not be in a place when someone else is there:
"We were late and missed the first part of the concert."
"I had to miss a week of school."
"We must have missed each other by about an hour."
To be going on = to happen
"I wonder what’s going on next door – they’re making a lot of noise."
To miss something = 何かに出席できない又は他の誰かがいる場所にいない
例文
"We were late and missed the first part of the concert."
私たちは遅れたので、コンサートの最初を見逃した。
"I had to miss a week of school."
学校を1週間休まなければいけなかった。
"We must have missed each other by about an hour."
私たちは、約1時間お互いにすれ違っていたに違いない。
To be going on =起こる
例文
"I wonder what’s going on next door – they’re making a lot of noise."
隣で何が起こっているのだろう。凄い音がしている。
Can you tell me what happened while I was away. There is so much of noise around this place now.
This place is quite noisy, can someone tell me what the noise is about?
Can you please tell me what's going on! I notice a lot of people speaking in low tones around here.
This place was quiet when I left for lunch....why has it become so noisy now? What happened while I was away?
例文
This place was quiet when I left for lunch....
私が昼食に出かけた時は静かだった。
why has it become so noisy now?
だけど今はどうしてそんなに騒がしいの？
What happened while I was away?
私が外出している間に何があったの？
What is going on - This is a direct way of asking about what is happening.
What have I missed while I was out - This is asking what did you miss while you was out of the office.
What is going on（どうしたの）
= これは単刀直入に、何があったのか尋ねています。
What have I missed while I was out（私がいない間に何があったの）
= これは、自分が会社にいない間に何があったのか尋ねています。
"What did I miss?" and "What happened?"
These two expressions are used when asking individual(S) what has happened? if they have missed something, often when you return somewhere you had very recently been and everyone there may be laughing and you would like to be 'Filled in' the expression to get the update on the situation, to see what had happened while you had left.
"What did I miss?"（何があったのですか）と "What happened?"（何があったのですか）
これら二つの表現はどちらも、「何があったのですか」と相手に確認するときに使われます。
"What did I miss?" は、例えば少しの間席を外して戻ってきたら、みんなが笑っている。自分がいない間に何があったのか確認したい。そんなときに使われます。
If there seems to be something that happened that everyone is talking about you can say that there seems to be commotion over something.
You can then go on to ask if there is something you missed, something you didn't learn.
Commotion: disturbance
Hype: heightened energy, excitement
"Hey, what's the hype about? Did I miss something?"
みんなが話していて、何かあったようなときには、何かざわついているねと言うことができます。そして何があったかを聞いてみましょう。
Commotion: ざわついていること
Hype: エネルギッシュなこと、興奮していること
"Hey, what's the hype about? Did I miss something?"
（ねぇ、何にざわついているの？何があったの？）
When you walk into an uncomfortable atmosphere without an obvious reason for it feeling awkward, it's easiest to just ask what happened there.
Sometimes to try and make light of the situation you can joke ask 'who died'- suggesting everyone looks so sad.
Asking a friend what is going on is another informal way of asking what is happening.
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