You can't know that.
How can you POSSIBLY know that?
The Big Bang Theory Season 2, Episode 19
How can I POSSIBLY go?
The Big Bang Theory Season 2, Episode 23
Or POSSIBLY Durham, North Carolina.
The Big Bang Theory Season 2, Episode 7
Events you couldn't POSSIBLY have anticipated
or prevented, even if you had.
Game of Thrones Season 5, Episode 7
how could I POSSIBLY choose
among the three of you?
The Big Bang Theory Season 11, Episode 12