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When Miss White was a student, she wanted to be a teacher, because she loved kids. So she studied very hard at school. She often read books in the library on the weekend. When she was twenty-five years old, her dream came true. She was an English teacher in a primary school.

One day, a girl in her class asked her, "Miss White, why does a man's hair become gray before his beard does?" Miss White laughed and said, "I don't know. Who knows?"

A boy stood up and said, "I know. A man's hair becomes gray first, because it's sixteen years older than his beard!"