
but the truth is,
Amy is just as CHALLENGING.
The Big Bang Theory Season 10, Episode 5

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

I know what a CHALLENGING man he could be,
The Big Bang Theory Season 9, Episode 14

"The CHALLENGING
climate of Scandinavia
The Big Bang Theory Season 12, Episode 23

- Just as CHALLENGING.
- Yes.
The Big Bang Theory Season 10, Episode 5