Maybe this is a question about forming some plural nouns or some third person singular verbs.
When a noun ends in "y" which follows a consonant (fly, flurry), in order to form the plural, change the "y" to "i" and add "-es." (flies, flurries)
When a verb ends in "y" which follows a consonant (fly, cry, carry, hurry), in order to form the third person singular form of the verb, change the "y" to "i" and add "-es."
(she flies, he cries, she hurries, he carries.)
For most nouns ending in "y," you change the "y" to "i" and add "es" to form the plural. For example, "city" becomes "cities" and "baby" becomes "babies."
Some words end in a consonant + y. To make them plural, change y to i and add es. Candy -> Candies
You drop the y and add ies to get libraries. You can also say - change the y to an i and add es.
Change the Y to I and add -es : the plural is poppies.
A herd animal that forms the plural by changing the 'y' to 'i' before adding the 'es' is pony - ponies.
This is because of the letters that precede 'Y'. When the 'Y' follows a consonant, the 'Y' must be replaced with 'I' and "ES" is added. When the 'Y' follows a vowel, only an 'S' is needed.
Change the y to an i and add -es.
Mortifies doesn't have a Y because when a word that ends in a Y becomes plural you change the Y to an I and add ES.
Some examples are "fry" becomes "fries," "study" becomes "studies," and "cry" becomes "cries." These words follow the rule of changing the 'y' to 'i' and adding 'es' when making them plural or third person singular.
Add -s to most nouns. Add -es to nouns ending in s, x, z, ch, or sh. Change -y to -i and add -es for nouns ending in consonant + y. Change f or fe to v and add -es. Memorize irregular plural forms like children, mice, and teeth.
Change the y to an i and add es.
Change the y to i and add es. For example, baby becomes babies.