Yeah, I BET it sucked.
The Big Bang Theory Season 7, Episode 4
I BET I can make
that girl president.
The Big Bang Theory Season 12, Episode 13
Bet you didn't know
that I had bongos.
The Big Bang Theory Season 5, Episode 18
and I'll BET you
dollars to donuts
The Big Bang Theory Season 5, Episode 18
...but I BET they look like this...
The Big Bang Theory Season 8, Episode 22