Spelling rules can get very complicated in the English language. However, the spelling rule for nouns ending in y is fairly straightforward. We will examine that spelling rule, some examples of its application and find out what the one exception is to that rule.
If a noun ends in a y that is preceded by a vowel, the plural is formed by simply adding an s to the word. For example, the noun monkey ends in a y preceded by the vowel e, so the plural is formed by simply adding an s as in monkeys. Other examples of this spelling rule are valley and its plural form, valleys, play and its plural form plays and boy and its plural form, boys.
If a noun ends in a y that is preceded by a consonant, the plural is formed by changing the y to an i and adding es to the word. For example, the noun baby ends in a y preceded by the consonant b, so the plural is formed by changing the y to an i and adding es, as in babies. Other examples of this spelling rule are city and its plural form cities, activity and its plural form activities, and lady and its plural form ladies.
There is one exception to this rule. The plural of a proper noun that ends in y is always formed by simply adding an s, whether the y is preceded by a vowel or consonant. This is true of the names of people as well as brand names. Some examples of this are the names Kennedy and its plural form Kennedys, Amy and its plural form Amys, and Hello Kitty and its plural form Hello Kittys.
The mother of the two dead boys, 24-year-old Lamora Williams, has been charged with two counts of murder, Atlanta police said. (The Atlanta Journal Constitution)
The county and its 31 cities are all raising taxes, according to a Sun Sentinel analysis of their budget and tax notices, for an average increase of 10 percent. (The Sun-Sentinel)
The Kennedys are particularly proud to have sponsored the local soccer team for more than 30 years. (The Nenagh Guardian)