一般规则是字母i在e前面，但在c之后除外：

believe sieve

但是：

deceive receipt

下面这些词例外，都拼写为ei：

beige                feint                  heir                 reign   their

counterfeit        foreign              inveigh            rein veil

deign                forfeit               inveigle            seize   vein

eiderdown        freight               leisure             skein   weigh

eight                heifer                neigh               sleigh  weight

either               height                neighbour        sleight weir

feign                heinous             neither             surfeit weird