
Hey, if you guys need a FOURTH, I'll play.
The Big Bang Theory Season 1, Episode 7

Dr. Fowler, you would be
only the FOURTH woman
The Big Bang Theory Season 12, Episode 19

It's May the FOURTH.
The Big Bang Theory Season 7, Episode 22

If you'd let me invite Penny,
you would've had your FOURTH.
The Big Bang Theory Season 1, Episode 7

If it's half as much fun as One Times Ten to
the Fourth Bottles of Beer on the Wall, I'm in.
The Big Bang Theory Season 8, Episode 19