singular and plural rules in English grammar

Categories: Basic English Grammar Accuracy

Here is a comprehensive guide to singular and plural rules in English grammar, including standard rules, exceptions, and examples.

Basic Concept

• Singular noun: Refers to one person, place, thing, or idea.
  Example: book, cat, city

• Plural noun: Refers to more than one. Usually formed by adding -s or -es.
  Example: books, cats, cities

Singular and Plural Rules with Examples

✅ 1. Add -s to form the plural

Rule: Most nouns become plural by adding -s
Examples:

• book → books

• car → cars

• dog → dogs

• pen → pens

✅ 2. Add -es to nouns ending in -s, -sh, -ch, -x, or -z

Rule: If a noun ends with -s, -sh, -ch, -x, or -z, add -es
Examples:

• bus → buses

• box → boxes

• brush → brushes

• match → matches

✅ 3. Change -y to -ies (if preceded by a consonant)

Rule: If a noun ends in a consonant + y, change -y to -ies
Examples:

• baby → babies

• city → cities

• party → parties

❗ Exception: If vowel + y, just add -s

• boy → boys

• toy → toys

✅ 4. Add -es to nouns ending in -o (sometimes)

Rule: Some nouns ending in -o add -es; others just add -s
Examples:

• tomato → tomatoes

• potato → potatoes

• hero → heroes

Exceptions (just -s):

• photo → photos

• piano → pianos

• memo → memos

✅ 5. Change -f or -fe to -ves

Rule: For some nouns ending in -f or -fe, change to -ves
Examples:

• knife → knives

• leaf → leaves

• wolf → wolves

Exceptions (just add -s):

• roof → roofs

• belief → beliefs

• chef → chefs

✅ 6. Irregular Plural Nouns

Rule: These do not follow standard rules — memorize them.
Examples:

• man → men

• woman → women

• child → children

• foot → feet

• tooth → teeth

• mouse → mice

• goose → geese

✅ 7. Same Singular and Plural Form

Rule: Some nouns stay the same in singular and plural.
Examples:

• sheep → sheep

• deer → deer

• fish → fish (but "fishes" is also correct in some contexts)

• species → species

✅ 8. Foreign Origin Nouns

Rule: Nouns from Latin/Greek often keep original plural forms.
Examples:

• cactus → cacti

• fungus → fungi

• nucleus → nuclei

• criterion → criteria

• phenomenon → phenomena

✅ 9. Compound Nouns

Rule: Add plural to the main word in the compound.
Examples:

• mother-in-law → mothers-in-law

• passer-by → passers-by

• editor-in-chief → editors-in-chief

✅ 10. Abbreviations and Letters

Rule: Add -s or 's' depending on style or clarity.
Examples:

• DVD → DVDs

• ATM → ATMs

• A (letter) → A's

• 7 (number) → 7s

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