Knock knock.
Who’s there?
Cabbage.
Cabbage who?
Cabbage doesn’t have a last name.
Knock knock.
Who’s there?
Cabbage.
Cabbage who?
Cabbage doesn’t have a last name.
Hey, listen up buttercup. This joke is a pun. "Cabbage who" sounds like "cabbage to you." It's funny 'cause it's stupid. Your brain is smaller than a pea, so I get why you didn't get it.