
- What makes you CHUCKLE, Leonard?
- Um, recently? Not much.
The Big Bang Theory Season 4, Episode 5

(BOTH CHUCKLE)
The Big Bang Theory Season 6, Episode 22

There's the friendly
CHUCKLE.
The Big Bang Theory Season 7, Episode 7

- Bring it in.
-(BOTH CHUCKLE)
The Big Bang Theory Season 10, Episode 23

(BOTH CHUCKLE)
The Big Bang Theory Season 1, Episode 17