英语专业四级阅读理解基础训练英语专业四级阅读理解基础训练successcoversamultitudeofblunders.以下是小编为大家搜索整理的英语专业四级阅读理解基础训练，希望能给大家带来帮助!更多精彩内容请及时关注我们应届毕业生考试网!Certainlynocreatureintheseaisodderthanthecommonseacucumber.Alllivingcreature，especiallyhumanbeings，havetheirpeculiarities，buteverythingaboutthelittleseacucumberseemsunusual.Whatelsecanbesaidaboutabizarreanimalthat，amongothereccentricities，eatsmud，feedsalmostcontinuouslydayandnightbutcanlivewithouteatingforlongperiods，andcanbepoisonousbutisconsideredsupremelyediblebygourmetsForsomefiftymillionyears，despiteallitseccentricities，theseacucumberhassubsistedonitsdietofmud.Itisadaptableenoughtoliveattachedtorocksbyitstubefeet，underrocksinshallowwater，oronthesurfaceofmudflats.CommonincoolwateronbothAtlanticandPacificshores，ithastheabilitytosuckupmudorsandanddigestwhatevernutrientsarepresent.Seacucumberscomeinavarietyofcolors，rangingfromblacktoreddishbrowntosandcolorandnearlywhite.Oneformevenhasvividpurpletentacles.Usuallythecreaturesarecucumbershaped-hencetheirname-andbecausetheyaretypicallyrockinhabitants，thisshape，combinedwithflexibility，enablesthemtosqueezeintocreviceswheretheyaresafefrompredatorsandoceancurrents.Althoughtheyhavevoraciousappetites，eatingdayandnight，seacucumbershavethecapacitytobecomequiescentandliveatalowmetabolicrate-feedingsparinglyornotatallforlongperiods，sothatthemarineorganismsthatprovidetheirfoodhaveachancetomultiply.Ifitwerenotforthisfaculty，theywoulddevourallthefoodavailableinashorttimeandwouldprobablystarvethemselvesoutofexistence.Butthemostspectacularthingabouttheseacucumberisthewayitdefendsitself.Itsmajorenemiesarefishandcrabs，whenattacked，itsquirtsallitsinternalorgansintowater.Italsocastsoffattachedstructuressuchastentacles.Theseacucumberwilleviscerateandregenerateitselfifitisattackedoreventouched;itwilldothesameifthesurroundingwatertemperatureistoohighorifthewaterbecomestoopolluted.1.Accordingtothepassage，whyistheshapeofseacucumbersimportantA.Ithelpsthemtodigesttheirfood.B.Ithelpsthemtoprotectthemselvesfromdanger.C.Itma