A handout on irregular plural noun forms

Exception 1:
Nouns that 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:

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