That's the thing about....

How would your conlangs translate the English idiom "That's the thing
about X..."?
It seems pragmatically to be, among other things, an affirmative response when
someone has made an observation about something, and you reply with this
saying their observation is generalizable to all X where X is a superset of the
specific thing/situation they were talking about.  Or you use it to
preface a general
observation about all X.

I've heard a very similar expression used in Esperanto, "Tio estas la
afero pri X...";
I'm not sure how common it is or if it's an anglicism (usonianism?) to
be avoided.

In gjâ-zym-byn I think I would render it as,

X ŝu-i Φĭ hum-ga-bô gǒ.
X property-of quality deep-METAPH-ADJ behold
Behold an important quality of X.

or, depending on the context and semantic details of the specific use of
said idiom to be translated, maybe

X ŝu-i hu gǒ.
X property-of essence behold
Behold the essence of X.

--
Jim Henry
http://www.pobox.com/~jimhenry/

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