Why do some words end in -s and others in -es?

The choice between -s and -es is primarily about pronunciation . English speakers add -es to words ending in hissing or buzzing sounds (like s, sh, ch, x, z) to create a new, distinct syllable. Without that extra syllable (like in box → boxes), the plural would be physically difficult to pronounce and hear.

Are "fish" and "fishes" both correct?

"Fish" is the standard plural form when talking about one or more fish of the same species. "Fishes" is a more specialized term, used primarily in scientific contexts to refer to multiple different species of fish. For almost all everyday conversations, just use "fish." See our guide: Fish or fishes: Which plural should you use?

Why do some plurals change completely (like "child" to "children")?

These are known as irregular plurals. They are remnants of Old English and other Germanic languages that predate the standard -s suffix. Because they don't follow modern rules, they are best learned as vocabulary words rather than grammar rules.

Can I add an apostrophe to make a word plural (e.g., "OG's")?

No. In standard English, an apostrophe indicates possession (e.g., the dog's toy), not plurality. Adding an apostrophe to a regular plural noun (like "OG's" instead of "OGs") is a common mistake even among native speakers; always stick to the plain -s or -es for plurals.

How do I know if a noun is "uncountable"?

Uncountable nouns represent abstract concepts, mass materials, or groups (like information, advice, furniture, or water). A simple test is to ask: "Can I count this with a number?" You can have three books, but you cannot have three advices. If you cannot count it directly, it is likely uncountable and does not take a plural -s.