Unit7TheSeaKillerwhaleshavethesecondheaviestbrainsamongmarinemammals(afterSpermwhales,whichhavethelargestbrainofanyanimal).Theycanbetrainedincaptivity(囚禁；关押)andareoftendescribedasintelligent,althoughdefiningandmeasuring“intelligence”isdifficultinaspecieswhoseenvironmentandbehavioralstrategiesareverydifferentfromthoseofhumans.Killerwhalesimitateothers,andseemtodeliberatelyteachskillstotheirkin.OfftheCrozetIslands,motherspushtheircalvesontothebeach,waitingtopulltheyoungsterbackifneeded.Peoplewhohaveinteractedcloselywithkillerwhalesoffernumerousanecdotesdemonstrating(证明)thewhales'curiosity,playfulness,andabilitytosolveproblems.AlaskankillerwhaleshavenotonlylearnedhowtostealfishfromIonglines,butalsohaveovercomeavarietyoftechniquesdesignedtostopthem,suchastheuseofunrated(未分级的；未征税的)linesasdecoys.Once,fishermenplacedtheirboatsseveralmilesapart,takingturnsretrieving(恢复；取回)smallamountsoftheircatch,inthehopethatthewhaleswouldnothaveenoughtimetomovebetweenboatstostealthecatchasitwasbeingretrieved.Aresearcherdescribedwhathappenednext:Thekillerwhale'suseofdialectsandthepassingofotherlearnedbehavioursfromgenerationtogenerationhavebeendescribedasaformofanimalculture.Section_ⅠWarmup__&_Lesson_1_—_PrereadingVIKINGVOYAGES①TOAMERICATheVikings②werethefirstEuropeanstoreachAmerica③.Theyachieved④thislongbefore⑤Columbuseversetsail⑥.TheVikingswereagroupofpeoplewhoseancestors⑦camefromScandinavia⑧.TheycontrolledtheseasandcoastsofNorthernEuropebetweenthe8thand10thcenturiesAD⑨.Byaround900AD,thereweremanyplacesinNorthernEuropewheretheVikingschosetolive⑩.In982AD,whenamancalledErictheRed⑪decidedtosetsailfurther⑫west,therewereasmanyas10,000VikingslivinginIceland⑬.①voyage/'vIId/ɔʒn．航海；航空②Viking/'vaIkI/ŋn．维京人，北欧海盗③名词中心词被序数词或thelast等修饰时，其后通常用动词不定式作后置定语。④achievevt.实现，到达achievementn．成就，功绩⑤longbefore很久以前beforelong不久以后⑥setsail启航⑦ancestor/'ænsεst/ən．祖先，祖宗⑧whose引导的定语从句，修饰agroupofpeople。⑨ADn．公元BCn．公元前⑩where引导的定语从句，修饰NorthernEurope。⑪过去分词作后置定语。⑫further/'fð/ɜːəadv.更远，较远further是far的比较级。⑬现在分词短语作后置定语。北欧海盗航行到美洲[第1～2段译文]北欧海盗是第一批到达美洲的欧洲人。早在哥伦布启航之前，他们就已经到达那里了。北欧海盗的祖先来自斯堪的纳维亚半岛。公元8世纪到10世纪期间，他们控制着北欧海面和沿海地区。大约到公元900年，北欧很多地方都有海盗居住。公元982年，一个叫埃里克·雷德的人决定向西远航。此时，冰岛生活着多达10000名北欧海盗。Accordingto⑭theoldstoriesofIcelandandNorway，ErictheRedwasforcedtoleaveIcelandbecausehehadcommittedamurder，⑮forwhichhegotintotrouble⑯.EricreachedGreenlandanddiscoveredthatpeoplecouldliveintheplacewherehelanded.HereturnedtoIcelandandtoldpeoplethereaboutGreenland.Hepersuaded⑰somepeopletogobackwithhimtoGreenland.Ericsetsailonceagain，thistimewith25ships，ofwhichonly14madeitto⑱Greenland⑲.NotlongafterErictheRedhadlandedinGreenland⑳，amancelledBiarnisetsailfromIcelandinsearchof○Eric'sparty.BiarniwashopingtojoinhisfatherwhowaswithEric,buthewasblownoff○course○andfoundhimselfin○anunknown○land，fromwhereheeventually○reachedGreenland○.⑭accordingto根据，依照⑮forwhich引导非限制性定语从句，for表示原因，which指代先行词amurder。⑯getintotrouble陷入麻烦，陷入困境⑰persuade/p'sweId/əvt.说服，劝服persuadesb.todos...
