第三章

**Duration:**Chtproteislimitedinduration.Afteracertainperiod,usuallytheauthor''''slifetimeplusasetnumberofyears,theworkehepubliainandbefreelyusedbyanyone.

    2.**FairUse:**Fairuseallowslimiteduseofchtedmaterialwithoutpermissionfromthechtholderforpurposessuchascriticism,entary,newsrep,teag,schorship,orresearch.

    3.**Publiain:**Worksinthepubliaiprotectedbychtwandbefreelyusedbyanyoneforanypurposewithoutpermission.

    4.**pulsoryLises:**Insomecases,goversmaygrantpulsorylises,allowingotherstousechtedworksundercertainditions,ofteninexgeforpaymentofroyalties.

    5.**SpecificExceptions:**Chtwsmayincludespecificexceptionsforcerta