And Leonard just stood
there with a big, dumb
SMILE on his face,
The Big Bang Theory Season 12, Episode 12
SMILE.
The Big Bang Theory Season 7, Episode 4
Just SMILE and laugh.
The Big Bang Theory Season 5, Episode 4
(LILY ALLEN'S "SMILE" PLAYING
OVER SPEAKERS)
The Big Bang Theory Season 1, Episode 1
Wipe that smug SMILE off your face.
The Big Bang Theory Season 9, Episode 9