irregular plural noun forms

in english, nouns are divided between the singular and plural form. to make a noun plural, an ’s’ is usually added to the singular but there are several exceptions to the rule.
 
exception 1:
nouns that end in ch, s, sh, x, or z form the plural by adding ’es’ to the singular. it’s BECause these words which end in ch, s, sh, x or z would be difficult to pronounce if only an ’s’ were added. here are some examples: $?d46.E~v)X.\=k' [ 本 资 料 来 源 于 贵 州 学 习 网 外语园地英语学习 http://Www.gzU521.com ] $?d46.E~v)X.\=k'

branch branches
fox foxes
bus buses

exception 2:
nouns that end in ’y’ which are preceded by a consonant form the plural by changing the ’y’ to ’i’ and then adding an ’es’. here’s an example:

city cities

exception 3:
nouns that end in ’f’ form the plural by changing the ’f’ to ’v’ and then adding an ’es’. here are some examples:

half halves
leaf leaves
thief thieves
wolf wolves

exception 4:
nouns that end in fe form the plural by changing the f to v and then adding only an ’s’. here are some examples:

knife knives
life lives

finally, there are many irregular plural noun forms which one must commit to memory. here are some examples:

man men
woman women
child children
tooth tooth
foot feet
louse lice
mouse mice
ox oxen
goose geese