动词后面加了ed后,ed怎么和原单词发音?

规则动词过去式加“ed”后的发音规则：
在浊辅音和元音后面 [d]
called borrowed
moved[mu:vd] enjoyed
welcomed
answered
在清辅音后面 [t]
asked
finished
helped[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
清：／p／／t／／k／／f／／F／s／／W／／tF／／ts／／tr／
浊：／b／／d／／g／／v／／V／／z／／T／／dV／／dz／／dr／
补充说明：
规则动词的过去式由“动词原形+-ed”构成,具体变化有：
1.直接在词尾加-ed.如:want—wanted,
work—worked,need—needed,clean—cleaned
2.以不发音的e结尾的在词尾加-d.如：like—liked,
live—lived,use—used,move—moved
3.
以一个元音字母加一个辅音字母结尾的重读闭音节动词,先双写结尾的辅音字母,再加-ed.如：stop—stopped,
trip—tripped
4.
以辅音字母加y结尾的动词,先把y变成i,再加-ed.如：study—studied,carry—carried,
hurry—hurried,marry—married
不规则动词的过去式大体上归纳有以下六条记忆法：
1.以t结尾的词,过去式与原形相同.如：put—put,let—let,
cut—cut,beat—beat
2.以d结尾的词,把d变成t.如:build—built,
lend—lent,send—sent,spend—spent
3.以n结尾的词,在词后加t.如：mean—meant,
burn—burnt,learn—learnt
4.以ow / aw结尾的词,把ow /
aw变成ew.如：blow—blew,draw—drew,know—knew,grow—grew
5.含有双写字母的词,将双写改为单写,在词尾加t.如：keep—kept,
sleep—slept,feel—felt,smell—smelt
6.含有元音字母o / i的词,将o / i变成a.如：sing—sang,
give—gave,sit—sat,drink—drank
备注：摘自2001年的《九年义务教育三年制初级中学英语教科书》语法部分.