词的复数不同形式的,比如library的复数是libraries等等等等

tooth- teeth
sheep- sheep
woman- women
mouse- mice
fish- fish
glass- glasses
wolf- wolves
sangwich- sangwiches
policeman- policemen
fridge- fridges
baby- babies
radio- radios
leaf-leaves
farm- farms
factory- factories
ship- ships
thief- thieves
knife- knives
cloth- clothes
German- German
child---children
foot---feet
tooth---teeth
wife---wives
life---lives
half---halves