[originaltext] Jack London was a famous American writer. He was born on Janua

Jack London was a famous American writer. He was born on January 12, 1876, in San Francisco, California. His family was very poor, and Jack had to leave school to make money. He worked hard in many different jobs.
   Later, Jack returned to school, but he didn’t stay. He wrote, "Life and pocketbook were both too short."
   In 1897, he went to Alaska to find gold. Instead, he found ideas there for his books and stories. He returned home and started to write. His writings were successful, and he became rich and famous in his twenties.
   Jack London was not a happy man, however. In poor health, he took his own life in 1916 . He was only 40 years old.
As a child, why did Jack leave school?