A suffix is added to the end of a word to make the word brand new
A suffix is added to the end of a word because that's just what they do
When words end in a 'y' that have a vowel right before
Just simply add an 's' to go from singular to plural
Day becomes days
Boy becomes boys
Monkey becomes monkeys
Valley becomes valleys
Keep going, you can do this
When words ending in a 'y' are preceded by a consonant
Drop that 'y' like a hot potato and add an 'ies
Party becomes parties
Family becomes families
Country becomes countries
Puppy becomes puppies
That's how you add"s" and"ies" to the end of a word