Intimacy in any form
has been CHALLENGING for me,
The Big Bang Theory Season 9, Episode 11
Oh, we'll make the puzzles
extremely CHALLENGING
The Big Bang Theory Season 9, Episode 8
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
It's like me CHALLENGING you
to a sexy pants contest.
The Big Bang Theory Season 8, Episode 19