阅读短文, 根据短文内容回答问题。(共10分，每小题2分)

Mark Twain was the pen name of Samuel Langhorne Clemens. He was born on November 30, 1835, in a small town in Florida, the USA. He grew up with a few naughty boys who later appeared in his stories. Perhaps you are familiar with some of his books, as The Adventures of Tom Sawyer and The Adventures of Huckleberry Finn. At the age of 12, his father died, and he began to work, first as a printer, then a pilot on a river boat. Those years on the boat went into his book Life on the Mississippi.
During the Civil War he worked as a reporter and used Mark Twain as his pen name. The stories he wrote in this period made him famous and popular. He made a lot of money by writing, lecturing and running his own publishing house. But he spent all of it on his high living and unsuccessful business.
Mark Twain was known as a world-wide famous writer and a humorist, which means funny man. But in fact, he took a serious view of life. Many sad things happened in his own life. All his experiences helped to shape his stories which showed the dark side of the society. He died as an old man of 75 in 1910.  (200)
What did Mark Twain do when he was 12?
Did Mark Twain write himself and his friends in his stories?
When did Mark Twain become famous?
What is Mark Twain’s writing style?
What does the passage mainly tell us and what does the writer think of Mark Twain?