
...only one of WHICH is true,
and we don't tell you WHICH one it is...
The Big Bang Theory Season 6, Episode 19

...WHICH train should I get on?
The Big Bang Theory Season 8, Episode 21

O is for outstanding, WHICH he is such.
The Big Bang Theory Season 4, Episode 7

but they'll fight if
they're well paid, WHICH they will be.
Game of Thrones Season 7, Episode 5

...WHICH would be evidence
of a planet orbiting it.
The Big Bang Theory Season 4, Episode 9