When I broke up with Penny,
I got back into my CELLO...
The Big Bang Theory Season 4, Episode 3
How do you meet girls playing the CELLO?
The Big Bang Theory Season 6, Episode 18
You mean my CELLO.
The Big Bang Theory Season 1, Episode 5
I guess he forgot that
I play the CELLO.
The Big Bang Theory Season 11, Episode 13
Leonard, you'll play your CELLO.
The Big Bang Theory Season 2, Episode 12