Translation:Why do your ears hurt?
The form んです is used here to express emotion (anxiety). Without this the question would sound plain and rational, e.g. A nurse asking a doctor about the ear pain of a patient.
There are other usages of this form.
Precisely, it is いたいのですか itai no desu ka. But as the omission, it becomes いたいんですか itai n desu ka. You can see the similar cases often in Japanese.
It sounds like you are asking somebody who hurts his ear(s) why.
If you want to ask a doctor why your ear hurts, i recommend 耳が痛いんですが、何故ですか？
Note: people don't normally write なぜ as 何故. I used to write ください as 下さい until my professor corrected me lol
Whats wrong with 下さい？ I have it on my motorbike brake liquid reservoir and also on my HP printer, so I guess japanese natives tend to use it.
(but this is offtopic, so I shouldn't probably ask that here)
Would "Why do ears hurt?" also be a possible translation? I know that it is quite a strange question to ask but still.
You might try specifying left/right to imply that only that one hurts. That seems to be the least clumsy way of saying it in Japanese. 「(みぎ↔ひだり）かたの耳が痛いんです」
I recommend 右側(みぎがわ) の耳が痛いんです。or 右(みぎ)の耳が痛いんで。of course you can simply replace 右 with 左(ひだり) for left.
<sub>耳が痛いです。 </sub>どちらの耳ですか。 <sub>この耳です。 </sub>右のでか。 <sub>はい、そうです。 </sub>わかりました、チェックしましょう。
How would you express express general curiosity "why do ears hurt" compared to the (according to comments here) emphatic "What caused your ears to hurt?"
I think this is the right way to say it:
"Ippanteki ni mimi ga itamu no riyuu ga ari masu ka?"
"In general, is there a reason why ears hurt?"
Or casually (and more specifically):
"Ippanteki ni mimi ga itamu no riyuu ga nani desu ka?"
"In general, what are the reasons why ears hurt?"
Small corrections: 「一般的に耳が痛む理由がありますか?」- you don't put 「の」 「一般的に耳が痛む理由は何ですか?」- here, you don't put「の」and you should use 「は」instead of 「が」
The owner of the ears have not been specified. It doesn't have to be "you".
なぜ - why
耳 - ear
いたいん － いたい is a verb - "to hurt". Adding の turns いたい into a noun. Then の is shortened to just ん。You can also say 「なぜ耳がいたいのですか？」It's the same sentence, but afaik, japanese people tend to shorten things down and reduce unnecessary information from sentences, so that's why often the nominalizer の gets shortened down to just ん。
So, just like in english, you basically take the verb "to hurt" and turn it into a noun - "hurting". The same principle is in japanese.
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