Boys grow their fingernails long because they don't want to bother cutting them. Girls are attracted to boys, even at an early age. At an early age, boys are attracted to dirt. Baby girls often talk earlier than boys do. Before boys talk, they learn how to make machine-gun noises.
Girls turn into women.
Boys turn into bigger boys called men. A college professor asked his class a question. The student said. It would be wonderfully poetic if the color reflected sadness provoked by gray skies, if we were in symbolic mourning for a lost sunny day. It would be more prosaic, but still interesting, if we made umbrellas black to put a certain solidity, gravity, and seriousness in our lives.