Most nouns are easily made to mean more than one. You simply add “s.”
dog – dogs
cat – cats
book – books
Then there are those nouns that end in ch, s, ss, sh, x, and zz. Here we add “es.”
beach – beaches
lens – lenses
mess – messes
lash – lashes
box – boxes
fizz – fizzes
If a word has one or more consonants before ending in “y,” we change the “y” to “i” and add “es.”
lady – ladies
buddy – buddies
body – bodies
doily – doilies
If a word has a vowel before the final “y,” simply add “s.”
key – keys
play – plays
buy- buys
toy – toys
eye – eyes
Then we have some irregular cases that make life fun for us.
man – men
woman – women
child – children
foot – feet
louse – lice
house – hice ( hahaha) Just testing you to see if you’re paying attention. (Of course it’s house – houses.)
goose – geese
moose – meese (just kidding again)
Moose is one of those words that stays the same in singular and in plural forms. Other words that don’t change are:
deer
sheep
aircraft
elk
grouse,
and probably several others.
Here are some that are quite different. It seems the rules are all mixed up.
Potato and tomato both add “es” to become potatoes and tomatoes, and yet there are many words that end in “o” and simply add “s” to make the plural.
avocado – avocados
mango – mangos (These two are controversial and can be spelled avocadoes and mangoes, but my preference is without the “e.”)
piano – pianos
photo – photos (Please do not add and apostrophe before the “s.” It is not photo’s.)
radio – radios
Numbers, such as when you refer to decades simply add “s.” Not apostrophe “s.”
1970s
2000s
early 1900s
Most words ending in “f” change the “f” to “v” and add “es.”
leaf – leaves
life – lives
thief – thieves
BUT!
A few special ones simply add “s.”
chief – chiefs
fife – fifes
belief – beliefs
roof – roofs (it used to be rooves about 300 years ago)