あれは何だったの？
Are wa nan datta no?
In Japanese, "what was that?" is expressed as あれは何だったの？ (Are wa nan datta no?)
This phrase is used to ask for the identity of something seen or heard in the past.
Which one should you use?
While あれは何だったの？ asks for the identity of a specific thing, you might use どういうことでしょうか in formal settings if you actually mean "What does that mean?" Additionally, 何だっけ is a casual way of asking "What was that again?"
Is there a formal and an informal way to say it?
For a polite tone suitable for strangers or superiors, use あれは何でしたか？ In more formal settings, the expression 何だったのでしょうか is also available. For casual or informal situations, you can use 何だったの or 何だっけ.
How does it change in a sentence?
The particle の at the end of the sentence acts as an explanatory particle, which adds a tone of curiosity or a request for an explanation.
How do you pronounce it?
Are wa nan datta no?
Did you know?
- The phrase 何だっけ contains a grammatical 'forgetting' marker っけ which signals that the speaker is trying to recall information they once knew.
- In very informal settings, the entire phrase あれは何だったの？ can be shortened to just あれ？, with the rising intonation implying the rest of the question.
- In Japanese, the concept of 'that' is split into two words: それ (sore) for something near the listener, and あれ (are) for something far from both. Using the wrong one when asking 'what was that?' reveals your physical relationship to the object.
Examples in context
- 彼の発言は非常に奇妙でした。何だったのでしょうか？His statement was very strange. What was that?
- あの音、何だったの？What was that sound?
- すみません、もう一度言ってもらえますか？何だっけ？Sorry, can you say it again? What was that?
- あれは何だったの？Are wa nan datta no?What was that?
- さっきの音、あれは何だったの？Sakki no oto, are wa nan datta no?That sound just now, what was that?
- 暗い中でのあれは何だったの？Kurai naka de no are wa nan datta no?What was that thing in the dark?
Example conversation
Two friends are walking in a park at night when they hear a strange noise.
- 美咲 Misaki今の音、あれは何だったの？Ima no oto, are wa nan datta no?That sound just now, what was that?
- 蓮 Renわからない、少し怖かったね。Wakaranai, sukoshi kowakatta ne.I don't know, it was a little scary.
- 美咲 Misaki蓮君、あっちを見て！Ren-kun, acchi o mite!Ren, look over there!
- 蓮 Ren美咲、急にどうしたの？Misaki, kyuu ni dou shita no?Misaki, what's wrong all of a sudden?
