
I always got stuck on
the first CHALLENGE--
The Big Bang Theory Season 7, Episode 3

We accept your CHALLENGE.
Name a time and place.
The Big Bang Theory Season 2, Episode 12

You want a real CHALLENGE,
try keeping me from eating more of these.
The Big Bang Theory Season 10, Episode 22

She has set me a CHALLENGE
Vikings Season 1, Episode 9

Maybe you need to CHALLENGE
your motor skills.
The Big Bang Theory Season 10, Episode 22