
...indicating he's CHALLENGING
the ruling on the field.
The Big Bang Theory Season 3, Episode 6

The guy's a genius. Maybe you weren't
CHALLENGING enough for him.
The Big Bang Theory Season 6, Episode 6

Intimacy in any form
has been CHALLENGING for me,
The Big Bang Theory Season 9, Episode 11

Not CHALLENGING?
I was humiliating the man.
The Big Bang Theory Season 6, Episode 6

It really doesn't matter
as long as it's CHALLENGING.
The Big Bang Theory Season 10, Episode 22