Normally "y" is changed to "ies". There are exceptions, such as "journeys". Also personal names are not so changed: "Penny" becomes "Pennys", if you have more than one person named Penny.
When applying suffixes to words ending in "y" preceded by a consonant, change the "y" to "i" before adding the suffix, unless the suffix begins with an "i." For example, "happy" becomes "happiness" (changing "y" to "i" before adding "ness").
yummy
When adding a suffix to a word that ends in -y preceded by a consonant, the -y changes to -i before the suffix. For example, "happy" becomes "happier" and "cry" becomes "cries".
The "s rule" typically refers to the spelling rule that governs how s is used at the end of words. When a word ends in a vowel plus y, the plural form is created by simply adding an s (e.g., day → days). When a word ends in a consonant plus y, the plural form is created by changing the y to i and adding es (e.g., baby → babies).
by, my
When a suffix is added to a word ending in a consonant the y changes to an I.
When the word angry is changed into the adverb angrily, the y in angry becomes an i; the applicable rule is that when you add a suffix onto a word that ends in y, you change the y to an i.
The general rule for nouns ending in "y" preceded by a consonant is to drop the "y" and add "ies" to form the plural. Some examples are:city = citiesmemory = memorieslady = ladiesparty = partiesThe exception to this rule is for the names of people. If a name ends in "y", an "s" is added to the end of the word, whether the "y' is preceded by a consonant or a vowel; for example, the two Marys or the Kennedys.For nouns ending in "y" preceded by a vowel, an "s" is added to the end of the word to form the plural. Some examples are:chimney = chimneyskey = keystoy = toysway = ways
The basic rule is for nouns ending in 'y' preceded by a consonant, the plural is formed by dripping the 'y' and 'ies'. For nouns ending in 'y' preceded by a vowel, the plural is formed by adding 's' only. Why this came about, I do not know. Perhaps a question for the category 'word origins'.Some examples for nouns that drop the Y and add IES for plurals are:babiesdaisiesladiesstoriesdairiesfairiespartiescountriesSome examples for nouns that do not drop the Y for plurals:alleysboyschimneysdaysessaysjoyskeysmonkeys
When adding a suffix to a word that ends in -y preceded by a consonant, change the -y to -i before adding the suffix. For example, happy becomes happily, ready becomes readily.
The analogous word for trip ending with the vowel y could be journey.
they