The word fish.
That is actually debatable. Though you can use "fish" for both the singular and plural forms, "fishes" is not incorrect. But words that do not change in plural applications and are NOT debatable are "deer" and "moose".
Let's clarify a bit. Fish AND fishes are correct. Let me explain. You might say "I have one fish in my aquarium." or "I have two fish in my aquarium." So, when would you use "fishes"? You would use that term to describe the different types in the oceans. You would say "Of all the fishes in the ocean, the Blue Whale smells the best." If you had used "Of all the fish in the ocean, the Blue Whale smells the best.", you would be implying there was only one Blue Whale whereas in the first example, you are saying that of all species of fish, the species of Blue Whale smell the best.
The same can be said for "People" and "Peoples". "Of all the peoples in the world, the Eskimos are the coolest."
And for the record, I'm not sure the blue Whale smells any better than any other fish.
The plural form for a nouns that ends with -nx, such as sphinx, the plural form is sphinxes; add -es after the -nx.
The word tortoise forms a regular plural, tortoises.
The word your can be both plural and singular. You may say to one person, "Is that your car?" You would also say to a group of people "Are those your cars?" Either way, the form of your does not change. The word "yours" is not a plural. It is the possessive form of your.
A non-plural word, a word (noun or pronoun) that is not plural is singular, a word for just one.
the plural word is comedones
The noun change becomes changes for the plural.
The plural of "contributes" is "contributes." The word itself does not change in its plural form.
The plural form of "tongue" is "tongues."
The plural of "zen" is also "zen." The word "zen" does not change in the plural form.
the plural form of music is ........... music there is no physical change to the word
horse
Had is a verb, not a noun, and is both singular and plural.
The plural form of the word "cod" is "cod." It is considered both singular and plural, meaning that the word does not change when referring to more than one cod fish.
The plural form for a nouns that ends with -nx, such as sphinx, the plural form is sphinxes; add -es after the -nx.
The word tortoise forms a regular plural, tortoises.
the word 'sheep' remains the same in singular or plural form, for instance: "there is a sheep" "there are some sheep"
To make the French word "complète" plural, you would change it to "complètes." This involves adding an "s" to the end of the word.