马克·吐温(Mark Twain)，美国作家、演说家，真实姓名是萨缪尔·兰亨·克莱门(Samuel Langhorne Clemens)，马克·吐温是他的笔名。你知道其笔名的由来吗？
There were many humorists during his lifetime in America，but Mark Twain has been by far the best known and the most loved one.Do you know why the man's real name is more widely known as Mark Twain? There is a story behind the name，and it's really not humorous.
Mark Twain was an old term used on the river.It meant twelve feet，which indicated safe water.Sam Clemens would have been very familiar with the term，as he was a riverboat pilot.Sam Clemens first heard the term used for a signature on writings，from another pilot，an old man that liked to tell the younger pilots of his knowledge of the Mississippi River.His name was Isaiah Sellers.He also liked to send some advice，knowledge and opinions to local newspapers，and he signed them Mark Twain.
It was the year 1861.Since Captain Sellers was a character that many other pilots knew of，it followed that Sam would write up a very short funny play about the man，involving a trip that Sellers never could have made.It was for Sam's own amusement and for that of the others in his profession.
However，a man named Bart Bowen gave the play to one of the New Orleans newspapers.He and othersconsidered the play extremely funny.Captain Sellers saw and read the play，and was deeply hurt by it.He never published articles again，and Sam Clemens felt awful about the part he played in that play，however innocent he was in the play.
A few years later，in 1864，Sam heard of the passing of Isaiah Sellers，and decided he would use the retired name of Mark Twain for his signature on his works.It became not only a signature but a new identity for him.He adapted the name to himself，and soon became known as Mark Twain，on paper and in real life.
In fact，he loved to be a riverboat pilot so much that he never considered any other profession.He was convinced that he would be on the river all of his days.But the Civil War changed that.And it was astonishing that after his success as a writer，he still preferred the life of a riverboat pilot.
[阅读障碍词]
1．indicate v．暗示，表明
2．signature n．签名
3．involve v．涉及，包括
4．amusement n．娱乐；消遣
5．innocent adj.无辜的，天真的
6．profession n．专业
7．convince v．使信服
