读/+：/音的字母（组合）规则
1．er读作/+：/。
例：serve/s+：v/，person/'p+：sn/。再如：
her hers verb term mercy German certain servant service nervous perfect referobserve certainly perfectly Germany university
2．ir读作/+：/。
例：bird/b+：d/，thirty/'I+：ti/。再如：
sir shirt skirt dirt first third girl firm dirty thirsty birthday circle
3．ur读作/+：/。
例：nurse/n+：s/，church/tM+：tM/。再如：
burn turn fur hurt burst Thursday murder murderer further curtain surface re-turn
4．ear有时读作/+：/。
例：learn/l+：n/，earth/+：I/，search/s+：tM/，early/'+：li/，research/ri's+：tM/
5．or在w后读作/+：/。
例：word/w+：d/，work/w+：k/。再如：
works worse worst worth worm world worthy worship worker workshop