The SOLE clue:
"It's not what it looks like."
The Big Bang Theory Season 5, Episode 1
Imagine you're the
SOLE human being
The Big Bang Theory Season 5, Episode 21
Now, I am not saying that I should be
the SOLE decider of who you mate with.
The Big Bang Theory Season 1, Episode 15
...whose daughter, Lakshmi, Is flying In
for the SOLE purpose of meeting him.
The Big Bang Theory Season 3, Episode 7
He’s going to sue me
for SOLE custody of my daughter,
Money Heist Season 1, Episode 8