英语语音-unit-7-English-Nasals-Approximants-Lateral(s)

EnglishNasals,Approximants&Lateral(s)TheEnglishconsonantscanbeclassifiedaccordingtoplaceofarticulationmannerofarticulationvoicing,i.e.voicedorvoicelessNasals,Approximants&Lateral(s)Likethestops,thenasalsareallmadebyclosingthevocaltractatsomepointinthemouth.Unlikethestopsoranyothersoundsinthelanguage,thereisanopeningintothenasalcavityinthepronunciationsothatthesoundcanberesonatedthroughthenose.Thenasalconsonantsare/m/,/n/,and/ŋ/./w/,/r/,and/j/arecalledapproximantsbecauseitisanarticulationinwhichthearticulatorsapproacheachotherbutdonotgetsufficientlyclosetoeachothertoproduceacompleteconsonantsuchasastop,nasalorfricative./l/iscalledalateralbecauseduringitspronunciation,thepassageofairthroughthemouthdoesnotgointheusualwayalongthecentreofthetongue.Allophonicvariationsof/m/Syllabic:somethingLengthened,whenanarresting/m/isfollowedbyareleasing/m/:somemoreThelabiodnetalnasal,whenfollowedby/f/:comfortAllophonicvariationsof/n/Dentalizedbeforealabiodental/f/or/v/:inviteVelarizedbefore/k/or//:thinkSyllabic:buttonLengthening,when/n/arrestsandreleasesadjoiningsyllables:tennamesAllophonicvariationsof/ŋ/Thealveolar[n],whenfollowedbyanalveolar:takingtenSyllabic:lockandkeyAllophonicvariationsof/r/Devoicedasinvoicelessclusters:treatTheone-tapflap/r/:veryTheretroflexed/r/:rightTheback/r/,beforeorafter/k/or//:crategrey/l/-/r/，/r/和ri(日)对比Allophonicvariationsof/l/Syllabic:bottleClear-l,madewiththetongueintheclassicalfrontedposition:leaseDark-l,(thetonguetipandbladeinthepostalveolarposition):callDevoicedinconsonantclusterswithvoicelessstops:playThepost-palatal,orvelar/l/:milk