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

...Teens for Jesus
Fourth of July hoedown didn't count.
The Big Bang Theory Season 4, Episode 1

Her apartment's on the FOURTH floor,
elevator is broken, you're gonna...
The Big Bang Theory Season 1, Episode 2

...if you would be the FOURTH member
of our "Halo" team.
The Big Bang Theory Season 1, Episode 7

...I finally arrived at the
Fourth Annual Dixie Trek Convention...
The Big Bang Theory Season 3, Episode 5