Little snarky there,
Cello Lessons.
The Big Bang Theory Season 5, Episode 12
Are you cool
playing the CELLO?
The Big Bang Theory Season 7, Episode 6
...ever to be stuffed
into his own CELLO case.
The Big Bang Theory Season 4, Episode 18
Leonard, I didn't know
you played the CELLO.
The Big Bang Theory Season 1, Episode 5
...building computers
or practicing your CELLO...
The Big Bang Theory Season 8, Episode 22