souriwasaslavestate,andyoungTwainbecamefamiliarwiththeinstitutionofslavery,athemehewouldlaterexploreinhiswriting..InMarch1847,whenTwainwas11,hisfatherdiedofpneumonia(肺炎).Thenextyear,hebecameaprinter‘sapprentice(学徒).In1851,hebeganworkingasatypesetterandcontributorofarticlesandhumoroussketchesfortheHannibalJournal,anewspaperownedbyhisbrotherOrion..Whenhewas18,heleftHannibalandworkedasaprinterinNewYorkCity,Philadelphia,St.Louis,andCincinnati.Hejoinedtheunionandeducatedhimselfinpubliclibrariesintheevenings,findingwidersourcesofinformationthanhewouldhaveataconventional(传统的)school.At22,TwainreturnedtoMissouri..AsayoungmanTwainworkedasariverboatpilotontheMississippiRiver.Whenhestartedhiswritingcareer,SamuelClemensadoptedthename“MarkTwain,”whichmeanttwofathoms,asafedepthforariverboat.Picturesfrom.