GBT188023512019低压电涌保护器元件第351部分电信和信号网络的电涌隔离变压器SIT的性

Grammar动词过去式•①一般情况加ed.清音/t/•浊元/d/•t,d后面读/id/.•②以e结尾，加个d.arrive-arrived•③单元+单辅，双写辅音，再加ed.•stop-stopped•④以辅音+y结尾的单词，去y变i，再加ed.askeddiscussedfinishedhelpedlookedparkedpickedwatched/t//d/arrivedbreathedcalledcleanedenjoyedshowedturnedused•规则动词过去式加“ed”后的发音规则•清辅音：送气强，声带不振动。•浊辅音：几乎不送气，声带振动。（送气指从喉咙向口外送出气流）•转另一个PPT•（1）清辅音：／p／、／t／、／k／、／f／、／θ／、／s／、／W／、／t∫／、／ts／、／tr／，再加上／r／、／h／，合计12个。（2）浊辅音：／b／、／d／、／g／、／v／、／ð／、／z／、／3／、／d3／、／dz／、／dr／再加上／m／、／n／、／η／、／l／、／j／、／w／合计16个。在浊辅音和元音后面[d]calledborrowedmoved[mu:vd]welcomedanswered在清辅音后面[t]askedfinishedhelped[helpt]passed[pa:st]reached在[t]音后面[id]wanted['wCntid]started['sta:tid][d]音后面[id]needed['ni:did]counted['kauntid]0