高二英语Unit10自然灾害教案【Part1BackgroundKnowledge背景知识】TropicalcyclonesareknownastyphooninthewesternPacificandashurricaneintheAtlantic.Thesestormsmostoftendevelopinthelateraummerandautumnoverjustnorthandsouthoftheequator.IntheAtlanticoceanthereareusuallyaboutsixhurricanesandtensmallertropicalstormseachyear.Butthereisnowaytoknowforsurehowmanystormswillhappeneachyearandhowseveretheywillbe.IntheUnitedStates,expertsatthegovernmentagency,theNationlaHurricaneCenternearMiamiWatchforthedevelopmentofsevereweatherandwarnpeopleaboutthestorms.TheNationalHurricaneCenterdependsmainlyonmodernsatellitestoobservedevelopingstorms.ItalsousesinformationcollectedbypassengerairplanesandshipsandbyAmericangovernmentairplanes.Satellitepicturesgivethescientistsagreatideaaboutweatherinalargearea.Scientistsusecomlputerstoincreasethesizeofpicturesthatshowadevelopingstorm.Theystudythesepicturestolearnmoreaboutthestorm’sdirectionandspeed.TheNationalHarricaneCenter’sadivisoriesareconcernedmainlywithshipsintheoceanwhileastormismovingoverthewater.Butthecenter’sexpertsaremostfamousfortheirworkwhenahurricanebeginsmovingtowardsland.AtfirsttheNationalHurricaneCentermakespublicweatheradvisorieseverysixhours.Butasastormgetsclosertoland,theweatherwarningsaremadeeverythreehours.Expertsatthecenterareondutytwenty-fourhourseachdaytoprovidenewwarnings.【Part2KeyLanguagePoints重点难点】1．动词observe的用法▲observe在本课中意为“观察”“注意到”，后面跟名词、名词性从句或复合宾语。如：(1)Asachild,helikedtoobservethebehaviorofbirds.在童年时代，他喜欢观察鸟的习性。(2)Iobservedthatthewasverypaleandaskedhimwhatwasthematterwithhim.我发现他脸色苍白，问他哪里不舒服。(3)Ihaveneverobservedhimdootherwise.我从未看到过他有另外的做法。(4)Thedetectiveobservedthemantryingtoforcethedooropen.侦探看到那个人想强行打开门。▲observe可作“评论”“说……”解释。如：(5)“Badweather,”thecaptainobserved.“坏天气”，船长说道。(6)Heobservedtomethatourworkwasverywelldone.他对我说我们的工作完成得很好。(7)Ihavelittletoobserveonwhathasbeensaid.对所谈的这些，我提不出什么意见。(8)Heobservedthattheweathermightcontinuedryforsometime.他说这干旱的天气可能还要延续一段时间。用心爱心专心121号编辑1▲observe还有“遵守”“庆祝”“纪念”之意。如：(9)Theserulesmustbestrictlyobserved.这些规定必须严格遵守。(10)DoyouobserveChristmasDayinJapan?在日本你们过圣诞节吗？(11)AtOxford,studentsmustpayfinesforfailingtoobservecertainrules.在牛津大学，学生违反某些校规要付罚款。(12)Theyobserveasmanyastwelvefestivalsayear.他们一年的节日有12个之多。2．动词reduce的用法▲reduce意为“减少”“缩减”。如：(1)Therisingsunquicklyreducedthefog.升起的太阳很快驱散了晨雾。(2)Theonlywaytodothatistoreduceexpenses.做那件事的惟一方法是减少开支。(3)Somefatpeopletrytoreducetheirweight.一些胖人设法减肥。(4)Thepricewasreducedby10percent.价格降低了百分之三十。(5)Thedoctorgavethepatientpillstoreducethepain.医生给病人药片以止痛。(6)Thenewcanalwillreducethedistancebetweenthetwocitiesbyhalf.新运河将使两个城市的距离缩短一半。▲reduce常与介词to连用，意为“使……处于……状态”“使……变为……”。如：(7)Thetownwasreducedtoashesinthewar.战争中该城化为灰烬。(8)Hehasbeenreducedtoskinandbonesbyillness.他病得皮包骨头。(9)Thegreatfirereducedtheforesttoafewtrees.这场大火把这片树林烧得只剩下几株树。(10)Intheolddays,povertyreducedmanypeopletobegginginthestreet.旧社会，贫困使许多人沦落到沿街要饭的地步。【注...
