Translation guide
Used in questions to express surprise, disbelief, or emphasis, similar to 'in the world' or 'the hell'. In Japanese, this is expressed with specific question patterns and particles, not a direct translation.
The speaker is shocked, confused, or cannot believe something, and asks a question with strong emphasis.
The most common and versatile way to add 'on earth' to a question. 一体 (ittai) literally means 'what on earth' or 'in the world'. It can be used with any question word (何, 誰, どこ, いつ, なぜ, どうして, etc.) and in both polite and casual speech.
What on earth happened?
Who on earth said such a thing?
Where on earth are you planning to go?
Using なんだ (casual) or なんですか (polite) after a question word adds emphasis, similar to 'on earth'. It seeks an explanation and often conveys surprise or insistence.
Adding だろう (casual) or でしょう (polite) to a question word expresses wonder or speculation, often with a nuance of 'on earth' when the speaker is puzzled.
A stronger, more emphatic version of 一体. 全体 (zentai) means 'whole' or 'entire', so いったい全体 is like 'what in the whole world'. Used for extreme surprise or frustration.
What on earth are you thinking?
The speaker is not really asking for information but expressing annoyance, scolding, or emphasizing a point.
Combines 一体 with the explanatory なの/なんですか for a strong rhetorical effect. Often used when scolding or expressing exasperation.
What on earth are you doing!
What on earth do you mean by that?
Using って or というの after a question word can make the question sound more pointed or rhetorical, similar to 'what on earth do you mean by...'.
The speaker wants to ask something surprising or personal but softens it to be polite or less confrontational.
Using でしょうか instead of ですか makes the question more polite and less direct, suitable for formal situations or when asking about something potentially sensitive.
What on earth could be the problem?
Adding かな (gender-neutral, casual) or かしら (feminine, casual) to a question word expresses wonder or self-questioning, often softening the question. It can carry a nuance of 'I wonder what on earth...'.
What on earth happened, I wonder?
There is no direct Japanese equivalent of the phrase 'on earth'. Avoid literal translations like 地球上で (chikyūjō de), which means 'on the surface of the Earth' and is not used for emphasis.
What on earth are you doing?
一体 is the standard, neutral way to add emphasis. なんて can also express surprise or disbelief but is more like 'such a' or 'what a'. いったい全体 is stronger and more emotional, often used in anger or extreme confusion.
What on earth is wrong?
What on earth! (What a thing!)
What on earth is your goal?
In casual speech, you can sometimes convey the 'on earth' feeling just by stressing the question word and using a rising intonation, without any special particle. However, adding 一体 makes it explicit.
What on earth?!
How on earth did you do that?
Why on earth would you say that?
Where on earth have you been?
Who on earth is that person?
Why on earth didn't he come?
Who on earth said that?
誰が来るのかしら？
Who on earth is coming, I wonder?