What is the funniest joke or brain teaser?

The teacher talked about the word "milk" and explained that it refers to small things, such as "squab", "suckling pig" and "deciduous teeth". So he asked Xiao Ming to make sentences ... Xiao Ming said, "I am too young to cross the cleavage of more than one meter." The teacher is sweating. Xiao Ming added, "My family is so poor that I can only live with a chest of 50 square meters. Xiaotian was wrong. It should be like this: "My head is small, so I am a nipple". The teacher said I was dizzy. Xiao Ming and Xiaotian said in unison, "Teacher, you are not completely dizzy, you are just areola. "