Names end by "y" preceded by a vowel just add "s"
e.g: Boy - boys Monkey - monkeys
Toys - toys Day - days
Nouns end by "y" preceded by a consonant change the "y" into "i" and add "es
e.g.: a baby - babies Country - countries
Society - societies Lady - ladies
Some nouns ending by "f " or "fe" change the "f" to "v" and add "es"
e.g.: Wife - wives Knife - Knives
Thief - Thieves Life - Lives