Use of を with seemingly intransitive verbs describing emotions


> 何を悩んでいるの  
>  What is troubling you?

> 何をそんなに興奮しているんだ  
>  What are you so excited about?

I keep seeing sentences like the above where verbs, which seem to me to be
intransitive, are taking 何 as an object. Are these examples of a larger class
of cases where this happens? Can someone please explain what is going on with
the grammar here?

I feel that [this
question](https://japanese.stackexchange.com/questions/44176/using-%E4%BD%95%E3%82%92-with-
intransitive-verbs-
eg-%E4%BD%95%E3%82%92%E3%81%AB%E3%82%84%E3%81%A4%E3%81%84%E3%81%A6%E3%81%84%E3%82%8B%E3%81%AE)
must be related but I doubt there is any accusatory tone in the examples I am
looking at.




As pointed out in the comment section, the first sentence is a plain
transitive usage of 悩む.

For the second sentence, I do feel an accusatory overtone similar to that in 何
**を** にやついているんだ explained in the [linked
question](https://japanese.stackexchange.com/q/44176/5010):

  * 何 **に** そんなに興奮しているんだ → The speaker doesn't feel good or bad about that fact that the listener is excited, but he is simply curious why the listener is excited.
  * 何 **を** そんなに興奮しているんだ → The speaker is dubious and/or annoyed, and he thinks there is nothing the listener should be excited about.

Both of these would be translated into English as "What are you so excited
about?", but they are slightly different in Japanese, and the 何を version is
closer to a rhetorical question. (The difference is not huge. The former can
sound accusatory depending on the context.)




As pointed out in the comment section, the first sentence is a plain
transitive usage of 悩む.

For the second sentence, I do feel an accusatory overtone similar to that in 何
**を** にやついているんだ explained in the [linked
question](https://japanese.stackexchange.com/q/44176/5010):

  * 何 **に** そんなに興奮しているんだ → The speaker doesn't feel good or bad about that fact that the listener is excited, but he is simply curious why the listener is excited.
  * 何 **を** そんなに興奮しているんだ → The speaker is dubious and/or annoyed, and he thinks there is nothing the listener should be excited about.

Both of these would be translated into English as "What are you so excited
about?", but they are slightly different in Japanese, and the 何を version is
closer to a rhetorical question. (The difference is not huge. The former can
sound accusatory depending on the context.)

