
And I want you to know that
that is SINCERE. I do feel bad.
The Big Bang Theory Season 9, Episode 13

I sense that's not SINCERE,
although I have no idea why.
The Big Bang Theory Season 3, Episode 11

If you're interested in making
a SINCERE effort to be a good teacher...
The Big Bang Theory Season 8, Episode 2

Okay. Now, see you look SINCERE
but your words are completely false.
The Big Bang Theory Season 10, Episode 6

A, that was not a joke,
that was a SINCERE request.
The Big Bang Theory Season 6, Episode 24