Spelling Rules for Adding The Plural S to Singular Nouns

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• The general plurals rule: Usually add the letter s to the end of a singular noun to make it plural.
I’ll take this book; you can use those books over there.
We have one bedroom on the first floor and three more bedrooms on the second.
• In compound nouns, add s only to the main noun.
This family uses one air- conditioner and one washing machine.
Their neighbors use three air- conditioners and two washing machines.
I have one son-in-law; my friend Frieda has three sons-in-law.
• Add es to a noun ending with a whistling sound (s, sh, ch, x, z) to make it plural.
one bus – three buses, a church – many churches, a box – boxes, a buzz – buzzes
• If the singular noun ends with a consonant + y, drop the y, replace it with an i and add es. Don’t drop the y, if the y is preceded by a vowel.
Yes: one city – two cities, a baby – babies, a country – countries
No: a toy – toys, a day – days
Note: If the noun ending with a y represents a person or a country, add only s in any case.
John F. Kennedy was the most famous of the Kennedys. In 1963, he didn’t visit the two Germanys after giving his speech in West-Berlin.
• If the singular noun ends with a consonant + o, add es. If the o is preceded by a vowel, only add s to make the plural form.
Yes:a potato – five potatoes, a hero – heroes, an echo – echoes
No: a radio – radios, a studio – studios, a kangaroo – kangaroos