in Best Jokes Collection 25 Best Knock Knock Jokes that are Absolutely Hilarious 111.6k Views #18 It’s Opportunity – Knock, knock!– Who’s there?– Opportunity!– That is impossible. Opportunity doesn’t come knocking twice! Pages:Previous 12345678910111213141516171819202122232425Next See more Previous article The Tell-Tale Sign Next article Where’s My Tractor?