Collocations for incomprehensible - adj.

be, seem
remain
find sth
She found his accent virtually incomprehensible.

completely, totally, utterly
almost, nearly, virtually
largely
mutually
The language has widely differing and often mutually incomprehensible regional dialects.

to
Latin verse remained completely incomprehensible to me.

Incomprehensible is used with these nouns:
jargon