
...and did so
using a stern facial EXPRESSION.
The Big Bang Theory Season 4, Episode 24

but I think I'm just an EXPRESSION of...
The Big Bang Theory Season 9, Episode 11

Funny EXPRESSION, sleep tight. Ha-ha. Ha.
The Big Bang Theory Season 1, Episode 7

What exactly does that EXPRESSION mean,
"friends with benefits"?
The Big Bang Theory Season 2, Episode 21

I wanted to see the EXPRESSION
on your face
The Big Bang Theory Season 12, Episode 19