Nobody asks, 'who's there ' when you try and tell a knock knock joke.
An instagator!
Has that been tried yet
Tell them ISIS are Red Sox fans.
You use test tickles
Char-Jar Binks
'Can I join you?'
You have to drop the bomb twice before she gets the message.
Are you ticklish?"
Because they don't like random people knocking on their doors
Dind Dong
There's none. They both knock on the door, but never goes in!
That I will open the door
Nothing, because he is the one who knocks.
I am the one who Knock-knocks.