[tlhIngan-Hol] Sentence as subject

[mayqel qunenoS]

I remember reading somewhere (I think in the wiki), that sentence as
subject is not allowed.

However, I can't understand how someone can use a sentence as subject
in the first place.

Can someone write an example of a sentence as subject, so that I will
understand, what someone is supposed to avoid ?

thanks

qunnoq