Because she had a pun in the oven!
Because they are never well done.
On a pun.
It's not there.
You skip the punchline.
Punjabi-ng.
Disclaimer: I don't know how well this joke will work in English. What's yellow and lies in a pond? An excevator. You don't think this is funny? Neither does the operator.
In all 3 cases, someone forgot to pull it out.
The guy didn't pull it out fast enough!
The energy bill...
Because they have cotton balls.
A 2nd born.
A hot rod. NOTE: When I was about 5, I thought this was the funniest joke on earth.