高中英语 Unit 2 Sailing the oceans课件 新人教版选修9.ppt

sailingtheoceans unit2 words minimumpoleoverheadoffshoreoutwardsecuremagnetic adj 最小的 最低的n 地极 柱 杆adj 在头上的adv 在头顶上 在空中adj 离岸的 海面上的adj 外面的 向外的adv 向外 在外adj 安全的 可靠的adj 磁的 有磁性的 awkwardreferenceprecisesimplifyportableshortcomingupdatedtendencyreliable adj 难使用的 笨拙的n 参考adj 精确的 准确的vt 单一化 简单化adj 轻便的 手提的n 缺点 短处vt 更新n 趋向 倾向adj 可靠的 可信赖的 1whatisanavigator 2whatisthedifferencebetweenanavigatorandanexplorer warmingup inpairsdiscussthesequestions anavigatorexploresnewroutesacrossthesea anavigatorexploresthesea anexplorerdiscoversnewplacesonland 3lookatthesefamouspeople aretheynavigatorsorexplorers whatdoyouknowaboutthem zhenghe intheyearbetween1405and1433 sevenlargetreasurefleetssailedwestwardsonvoyagesoftradeandexploration underthecommandofzhenghe thefleetssetsailfromthesouthchina seaacrosstheindianoceantotheredsea andthentraveledfurthersouth discoveringtheeasterncoastofafrica herenewedrelationswiththekingdomsoftheeastafrican whenmarcopolowasstillveryyoung hedecidedtotraveltogetherwithhisfather ittookthemmorethanthreeyearstotraveltochina afternearlyseventeenyears travelintheeast marcoandhisfatherwantedtoreturnhome marcopolo marcopolowasborninvenicein1254 hewasthemostfamousforeignertovisitasiaduringthemiddleages jamescook 1728 1779 wasthegreatestbritainnavigator cookenlistedintheroyalnavy in1755 in1768hewaspromotedandsenttothepacificwherehesurveyedtahiti newzealand andaustralia onhisfamous2ndexpedition 1772 75 heexploredantarctica in1776inhisthirdandfinalvoyage heexploredthewestcoastofnorthamericaanddiscoveredthehawaiianislands navigatorissomeonewhofindsthepositionandplotsthecourseofaship anaircraft acar etc usingmapsandinstruments navigator sea nauticalinstruments findnewislandsorcontinents explorerissomeonewhotravelsintoorthroughaplaceinordertolearnaboutit veryoftennavigatorsarealsoexplorers explorer land useofcompassandlandmarks findnewplaceswithinanalreadyidentifiedislandorcontinent 1howdoyouthinkseamenfoundtheirwaybeforemodernaccuratemethodsofnavigationwereinvented pre reading lookatthepicturesonpage11 thenanswerthequestions keptclosetotheshore usednaturesuchasthesun wind birds tide etc tohelpthem andusedsomeoftheinstrumentsincludingacompass astrolabe etc 2whichdoyouthinkwaseasiertoworkout latitudeorlongitude latitude becauseitwasusedtomeasurehowfaryouhadtravelledfromlandonastraightline itwasdiscoveredalongtimebeforelongitude 3canyouidentifytheseearlynavigationalinstrumentsseamenusedandexplainhowtheyareused 1 2 3 4 compass inancientchina astrolabe sextant sea nautical marinechart 4whichonesdoyouthinkarestillusedtoday seachartsarestillusedtoday sailingtheoceans reading nowreadaboutwhatnavigationwaslikebeforemoderninstrumentswereused 1whatistheuseofabearingcircle astrolabe quadrantorsextant whatistheuseofacompass atosetthecourseoftheshipbtomeasurethepositionoftheshipctomeasurethespeedoftheshipdtotellthetime b a comprehending 1readthepassageandanswerthefollowingquestions speedandtimeareimportantinfindingoutthelongitudeofashipbecausetheearthmovesfifteendegreeswestwardseveryhour ifyouknowyourdirection speedandtime youcanworkouttheapproximatelongitudeorchangeinyourpositioninrelationtothestars whyarespeedandtimeimportantinworkingoutthelongitudeofaship thepositionofthesunandstarsareusefulforworkingoutlatitudebecausetheyarefixedpointsintheskyandtheirmovementsinrelationtotheeartharealreadyknown sotheycanbeusedtomeasureaship sposition 3whyisthepositionofthesunandvariousstarsusefulforworkingoutlatitude thesailorswouldneedtobeexcellentnavigators abletocopewithbothhotandcoldweather experiencedinsailingthroughverybadweatherandabletoco operateinateam 2supposeyouwereaseacaptainaimingtosailroundafrica discussingroups 1whatskillswouldyouseekinyoursailors iwouldanticipateveryhotweather aroundtheequator coldweather aroundthecapeofgoodhope verystormyseas aroundthecape andproblemswithfoodandwater unlesshelpedbylocalnativesthewatermaybecontaminatedandthefoodscarce etc whatproblemswouldyouanticipateforthisjourney sailingtheoceans usingnaturetokeepalongsidecoastlinepart1 usingnavigationalinstrumentstohelppart2 usingcelestialbodies usingthewildlife findinglongitude usingthesea findinglatitude usingtheweather 3whatwouldyoudoifyoucameacrossthefollowingproblemsduringyourvoyage readthechartbelowandfillinyourplansofactiontodealwiththem waittillthestormisover andthenfindyournewpositionandreturntoyouroriginalcourse useknotstofindyourspeedandworkoutyourapproximatelongitude usethecompassandtheastrolabe quadrantorsextanttofindoutyourposition returntoyourformercourse follownestingbirdstoshore lookforspecialcloudformationsorfogoverstreamstofindland useacompass measureyourpositionusingthesunorstars lookforseabirds cloudformations fogorseaweedtoshowthatlandisnearby tofindtheship spositionatseaasailorusedthenorthstarandthesun 4readthepassageagainandusetheinformationtoanalysethenavigationalskills writetheanswersinyourownwords usingnature 2asailorknewthatlandwasnearbyifhesaw 3sailorsused toincreasetheirspeed usinginstruments4thereweretwomethodstofindlongitude 1 2 measuringtimeandspeed compassandcomplicatedmathematicaltables 5writedowntheworkingprinciplesofthefollowinginstruments beatingcircle astrolabe tocomparetheheightofthesunnowwiththepositionofthe sunatmidday tocomparethepositionoftheshipinrelationtosomestarsorthesun quadrant amorepreciseformoftheastrolabe tomeasurehowhighstarsareabovethehorizon andcomparethatmeasurementwithpreviousmeasurements usingtheshipasoneofthefixedpointstofinditsposition sextant anupdatedversionofthequadrantandsoitwasmoreaccurate tomeasuretheanglebetweentwofixedpointsoutsidetheship usingtwomirrorstofindtheship sposition 5imagineyouareonaboatwithtwenty nineotherpeople youhaveasmallboxforyourpersonalthingsbutitcanonlyholdtenitems whatwouldyouneedforaweek sjourneyacrossthenorthseatoengland shirt trousers waterproofboots soap scissors knife blanket sea sicktablets coldmedicine cards chess novels essaycollections 1 atthemercyof听任 摆布 在 面前无能为力 theywerelostatseaatthemercyofwindandweather have showmercyonsb 宽恕或怜悯某人 withoutmercy毫不容情地 languagepoints avoid making anyreferencetohisillness 千万别提起他的病 2 referencen 提到 说到 涉及 附注 旁注 checkyourreferences要核对引证的资料 知识拓展 referv 提到 说起 涉及 参考 查询 常与to连用 whenisaidsomepeoplearestupidiwasn treferringtoyou 当我说某个人很愚蠢的时候 我没有提到你 ifyoudon tknowwhatthismeans pleaserefertothedictionary 如果你不知道这是什么意思 请查看字典 shesimplifiedtheinstructionssothatthechildrencouldunderstandthem 她简化了指令以便于儿童理解 3simplifyv 简化 使单纯 thatwillsimplifymytask 那可简化了我的工作 1 thedatashouldbeupdatedonceaweek 这些数据应该每星期更新一次 2 mapsneedregularupdates 地图需要经常修订 3 iupdatedthecommitteeonourprogress 我向委员会报告了我们的进展情况 4updatev 更新 补充最新资料 ssubject主语ppredicate谓语oobject宾语attattribute定语advadverbial状语comcomplement补语p