Plurals in English are easy, for the most part. Surely you already know the basic rules:
Group 1: Add an “-s”
Most nouns simply take an “s,” and there you are. Examples: girl/girls, boy/boys, bike/bikes, car/cars, meal/meals, college/colleges.
Group 2: Add an “-es”
For nouns that end in “-ch,” “-o,” “-s,” “-x,” or “-z” add “-es.” Examples: church/churches, potato/potatoes, tomato/tomatoes, pass/passes, fox/foxes, buzz/buzzes. Note that “bus” is pluralized in the same way: “buses.” I know it looks as if it rhymes with fuses and ruses, but it doesn’t. If you write “busses,” you are using an old-fashioned word for “kisses”; and, even though it may be acceptable to some as the plural of “bus,” it is wrong. Also, the “-o” family deserves a word of caution: Usually, you add “-es,” but not for words that are abbreviated forms of other words. Then, you just add “-s.” Examples: memo/memos (from “memorandum“), cello/cellos (from “violoncello“) and stereo/stereos (a prefix from another word, “stereophonic“).
Group 3: Changes in Spelling
The final “-f” or “-fe” changes to a “-ve” before adding the “s.” Examples: knife/knives, life/lives, loaf/loaves, self/selves. For some reason, “roof” no longer follows the rule, although a century ago you would encounter “rooves.” The words “proof” and “dwarf” are also mavericks: “proofs” and “dwarfs.”
The final “-y” changes to “-i” before adding “es” if the “y” was preceded by a consonant: Examples: party/parties, try/tries, baby/babies, fatality/fatalities. If the final “-y” is preceded by a vowel, just add an “s.” Example: valleys. Proper names ending in “y” just take an “s“: Example: “The McHenrys“; “How many Schenectadys are there in the U.S.?”
So far, so good. Now the tricky part comes in:
Group 4: Irregular Plurals
You already know most of these words, too, let us hope. You simply have to learn them. Most come from the Saxon side of English, and reflect Germanic plurals of long-standing. For example, “man” (or “husband”) in German is “Mann.” The plural is “Männer,” and is pronounced “men-er.” Common examples of irregular plurals: louse/lice, mouse/mice, goose/geese, man/men, woman/women, child/children, elk/elk, head (of cattle)/head, foot/feet, tooth/teeth. Some will say the plural of a computer mouse is “mouses.” That is really up to you to decide for yourself.
Group 5: Imported Words
Greek and Latin nouns are, in the main, made plural in English by following the inflection of the source language. If you haven’t studied Latin or Greek, then the only way to find your way around is to memorize these plural forms.
If the noun is of Greek origin, and ends in -on, the plural is -a. Examples: phenomenon/phenomena, criterion/criteria. Please don’t use “phenomena” or “criteria” with a single verb! More than one “neon,” however, is “neons.”
Some Greek nouns end in -a in the singular, like “drama” and “lemma.” Many of them, like “drama,” have been fully imported into English, so they follow the usual rules for plurals. The correct plural for “lemma” is still “lemmata.”
If the noun is of Latin origin, and ends in -a (feminine ending), the plural is “-ae.” Examples: alumna/alumnae, larva/larvae, nebula/nebulae. If the noun ends in -us (masculine ending), the plural is “-i.” Examples: alumnus/alumni, cactus/cacti, hippopotamus/hippopotami, anthropophagus/anthropophagi. If the noun ends in -um (neuter ending), the plural is “-a.” Example: datum/data, erratum/errata, medium/media, memorandum/memoranda, millennium/millennia. Note: some words are often used in the plural, but if the speaker is unaware that it’s a plural, he or she will use a singular verb. “Agenda” is the main culprit here, which is a neuter plural. It means, literally, “things that must be done.” So it is technically wrong to say “The agenda is long.” It would be correct to say, “There are many agenda.” If you can’t bring yourself to use agenda in the plural, but your conscience troubles you about using “is,” say “the list of agenda” instead. “Media,” on the other hand, is almost always used (correctly) in the plural: “The media were infatuated with the Duchess of York.”
Some Latin nouns end in something other than “-a,” “-us,” or “-um.” The “-sis” ending (from Latin’s third declension) is pluralized to “-ses.” Examples: crisis/crises; basis/bases. Be sure to pronounce the second syllable of the plural to rhyme with “knees.” A similar plural (“-ces“) applies to words ending in “-ex.” Examples: index/indices; appendix/ appendices.
Imported French words follow the same principle: Their plurals follow French rules, too, unless the word has become so acclimated to English that it adopts the English rules. Example: beau (meaning boyfriend or male escort). The plural is beaux. The “x” is not pronounced. (Mark Twain said, “The French always spell better than they pronounce!”) French usually pluralizes with an “-s” even though it is often tacit, so the issue of irregular plurals does not often arise with French words in English. (English obtained its “-s” plural by import from Norman French nearly a millennium ago , so it’s no surprise that the two languages still use the same basic rule for plurals.)
Group 6: Compound and Hyphenated Nouns
You should have learned in school that the plural of “mother-in-law” is “mothers-in-law.” That makes sense, because the noun is really “mother,” and the “in-law” part is a kind of adjectival suffix. The same is true with “lady-in-waiting” and “sergeant-major” (plural: “sergeants-major“). You can be one “passerby,” or if you are in the company of someone else, there will be two “passersby.” Most compound nouns, however, follow the usual rules for plurals because the final part of the compound is really the noun part. Examples: boatloads; six-packs; toothbrushes; bedrooms.
Group 7: Letters and Words, Numbers and Acronyms
Add an “s” to pluralize a letter, a number, a “word that refers to itself” (see below), or an acronym (pronounceable abbreviation).
An apostrophe is used only in the plural of letters of the alphabet, and the plural of self-referring words. These are words that are cited, rather than used for their meaning. Example: The word “worm” begins with “w.” The “worm” in quotes is a self-referring word.
In all other instances, do not use an apostrophe in a plural! Add “-es” to make plural an acronym ending in “-s.” Consider the following examples:
- Mind your p’s and q’s. (letters)
- The 1960s were a time of political change. (numbers)
- He used five “but‘s” in that sentence! (word that refers to itself)
- She has two PhDs, one in sociology and one in economics. (acronym)
- Does the test measure IQs over 120? (acronym)
- How many GPSes do you need? (acronym ending in “s”)
Tricky Questions of Verb Agreement
Almost all of the time, the singular noun will take a singular verb, and the plural noun will take a plural verb. However, in American Standard English, we usually use the singular with collective nouns, whereas the British use the plural. Compare: The team was ready to play (USA) versus The team were ready to play. (UK)
The general rule: If the collective noun is used, and the intention is to refer to each member individually, use the plural: The jury were confused by the testimony. If the intention is to refer to the whole group, use the singular: The jury has rendered its verdict.
Companies, sports teams and subjects of study are usually referred to in the singular, even if they end in “s.” Examples: Chrysler Motors owns the Jeep trademark; The Steelers is my favorite NFL team; Mathematics is not my favorite course; Gymnastics is fun to watch. Also, “news” is singular: “The news is not good today.” (My journalist father used to have a co-worker on the paper who would come to work every day and ask, just to be funny, “Are there any news?” My father would always reply, “Not a new.”)
In the U.S., “pants” is usually singular. In the U.K., “trousers” is plural. “Glasses” (meaning spectacles) is singular (really, it is “a pair of glasses”). “Scissors” is usually plural, though, like “glasses,” if used in the singular, it probably derives from “a pair of scissors.”
Numbers are plural if they represent more than one member of a group: “Thirty-five people have signed up.” They are singular if they represent one collection of things: “One-third has signed up.”