
The colors are BASED
on Star Trek: The Original Series.
The Big Bang Theory Season 1, Episode 13

...with a culture BASED loosely
on Earth's Athens and Sparta?
The Big Bang Theory Season 2, Episode 16

Well, BASED on what you told me,
I'm not surprised.
The Big Bang Theory Season 1, Episode 10

But BASED on everything
I've observed about us...
The Big Bang Theory Season 2, Episode 15

...which predicts the stability of a couple
BASED on behavior.
The Big Bang Theory Season 8, Episode 3