There are five main plural noun rules. Here they are:

1. You can form a plural noun by adding -s or -es to the end of the noun.
2. When a singular noun ends with a consonant followed by -y, you must change the -y to an -i and add -es.
3. Many nouns ending in—o will take an -s to form the plural, but some will require—es. If you’re unsure, consult a dictionary.
4. Most nouns ending in—f or—fe must change the—f to a—v and add—es to form the plural. Yet, there are a few exceptions where you only need to add -s.
5. Some nouns don’t follow specific rules for forming plurals. They’re called irregular plural nouns, and they have to be memorized.

Plural Noun Rules – Learn Now

Plural Noun Basics

A noun is a word that represents a person, place, thing, or idea. When a noun refers to just one thing, it’s a singular noun. But when a noun represents more than one person, place, thing, or idea, it becomes a plural noun.

For example:

• Singular noun: dog
• Plural noun: dogs

In this example, “dog” refers to a single canine, but “dogs” refers to two or more furry friends.

Understanding singular and plural nouns is key to clear English. You must use the correct noun to ensure your message is clear and accurate, and this is true whether you’re speaking or writing.

We use plural nouns in many contexts, from everyday talk to formal writing. They’re helpful because they allow us to discuss multiple entities without repeating the singular noun each time.

For example, instead of saying, “I have a cat, a cat, and a cat,” you can simply say, “I have three cats.”

Plural Noun Rules

Rule 1: The -s and -es Suffixes

The most common way to form plural nouns is by adding -s or -es to the end of the noun.

If a word ends in -s, -ss, -sh, -ch, -x, or -z, you must add -es to create the plural form. You can take a look at the following examples below:

I love eating pistachios as a snack during movies.

She collected seashells along the beach during her vacation.

The foxes quickly darted into the dense underbrush.

Rule 2: Dealing with -y Endings

When a singular noun ends with a consonant followed by -y, you must change the -y to an -i and add -es.

But, if the noun ends with a vowel and is followed by -y, simply add -s to form the plural. Take a look at these examples:

The babies were all sound asleep in their cribs.

I always bring extra batteries when I go camping.

The donkeys brayed loudly as we approached the farm.

Rule 3: The -o Ending Conundrum

Many nouns ending in—o will simply take an -s to form the plural, but some will require—es. If you’re unsure, consult a dictionary.

Example:

The avocados at the farmer’s market were ripe.

She carefully placed the tomatoes in her shopping basket.

The heroes were honored with a parade through the city streets.

Rule 4: Navigating -f and -fe Endings

Most nouns ending in—f or—fe must change the—f to a—v and add—es to form the plural. Yet, there are a few exceptions where you only need to add -s.

Example:

The thieves made off with the valuable paintings in the middle of the night.

I had to trim my cat’s claws because they were getting too sharp.

The chefs prepared an exquisite five-course meal for the banquet.

Rule 5: Irregular Plural Nouns

Some nouns don’t follow specific rules for forming plurals. They’re called irregular plural nouns, and they just have to be memorized. You can take a look at these examples:

The children were excited to visit their grandparents over the weekend.

I need to get my teeth cleaned at the dentist next week.

The geese flew south in a distinctive v-shaped formation.

Master these rules and familiarize yourself with the common exceptions. Then, you’ll be on your way to using plural nouns effectively in English. Just keep on practicing, and don’t be afraid to implement these rules!

Patterns of Irregular Plural Nouns

Irregular plural nouns do seem daunting at first. But, some helpful patterns can help you navigate through them. Once you get used to seeing these patterns, you can remember them more easily, and apply the correct plural forms in your English.

1. Vowel Changes

One common pattern among irregular plurals is the change in vowel sounds. Pretty simple, take a look at these here:

• “foot” becomes “feet”
• “goose” becomes “geese”
• “tooth” becomes “teeth”
• “mouse” becomes “mice”

In all these cases, the vowel sound in the singular noun changes when forming the plural. This pattern occurred in Old English, where more vowel changes were common in making nouns plural.

2. Latin and Greek Origins

There are also a lot of irregular plurals in English that come from Latin or Greek roots. These words often keep their original plural forms. Here’s some examples for you:

Latin: “radius” becomes “radii”

Latin: “syllabus” becomes “syllabi”

Greek: “criterion” becomes “criteria”

Greek: “phenomenon” becomes “phenomena”

You might be able to recognize these patterns if you’re familiar with Latin or Greek. Yet even if you don’t, you can still learn to memorize and identify them as you practice and study.

3. Unique Plural Forms

Some irregular plurals have unique forms that don’t follow any specific pattern. These words require memorization. Examples include:

“child” becomes “children”

“person” becomes “people”

“ox” becomes “oxen”

These words may seem difficult initially, but they will become easier to use with practice and exposure.

4. Unchanged Plurals

Another pattern to be aware of is nouns that remain unchanged in their plural form. These words are often animals or types of fish. For example:

“sheep” remains “sheep”

“fish” remains “fish”

“deer” remains “deer”

These words can be singular or plural nouns. But, they need a plural verb form when used in the plural sense.

List of Common Irregular Plural Nouns

These irregular plural nouns break the standard rules for plurals in English. Some of them undergo vowel changes. Just think of examples like “foot” becoming “feet” or “goose” becoming “geese.” There are still others, like “child” and “person,” which have unique plural forms. Again, you have to memorize them.

Singular Noun	Plural Noun
child	children
person	people
man	men
woman	women
tooth	teeth
foot	feet
mouse	mice
goose	geese
ox	oxen
basis	bases
radius	radii
syllabus	syllabi
phenomenon	phenomena
criterion	criteria
analysis	analyses
diagnosis	diagnoses
cactus	cacti
fungus	fungi
nucleus	nuclei
thesis	theses
axis	axes
crisis	crises
sheep	sheep
fish	fish
deer	deer
series	series
species	species

Learn these common irregular plural nouns. Memorization is the only way to master them correctly in speech and writing.

Sources

Grammarly