Dubious

Dubious

<do-be-us>

unsure; uncertain; unclear;

something in doubt with no clear answer.

Math is a dubious subject because I don't understand it.

Memory trick:
We dub something when we don't understand it.
dub means to make up words.

At work:
The report is dubious because I don't trust the numbers.

(c) 2015 E. Carruthers