1. A common noun is a person, place or thing;
2. A proper noun is easy to recognize because it is always capitalized.

Now on to plurals we go:

The plural of most words is formed by adding –s to the singular form of the noun:

• lake, lakes; sell, sells; crawl, crawls; shade, shades; the Browns; the Andersons; the Rothmans.

For common nouns ending in y and preceded by a vowel, add an –s:

• Sashay, sashays; bay, bays; cay, cays; day, days

For proper nouns ending in y, the plural is formed with the regular –s:

• the two Pattys; the two Scullys; the two Kansas Citys.

For common nouns ending in ch (soft), s, sh, x, and z, add –es:

• ch: churches, coaches, perches;

• s: glasses, masses, grasses;

• sh: pushes, lushes, crushes;

• x: hoaxes, boxes, foxes;

• z: buzzes, snoozes, quizzes.

For proper nouns like those above, also add –es:

• Charles, Charleses; Beech, Beeches; Cox, Coxes.

For common nouns ending in ch (hard) add only an s:

• monarch, monarchs; patriarch, patriarchs; epoch, epochs.

For common nouns ending in y and preceded by a consonant or qu, y changes to i and –es is added:

• army, armies; city, cities; heavy, heavies; levy, levies; soliloquy, soliloquies.

Proper names are the exception to the above rule:

• Kennedys, Murphys, McCreadys.

• exceptions to the proper name rule are well-known terms, like: the Rockies, the Alleghenies, and the Ptolemies.

For common nouns ending in y and preceded by a vowel, add an –s:

• Sashay, sashays; bay, bays; cay, cays; day, days

For proper nouns ending in y, the plural is formed with the regular –s:

• the two Pattys; the two Scullys; the two Kansas Citys.

For common nouns ending in -o, there are a couple different rules:

If a vowel comes before an –o ending, a plural is formed by adding –s to the singular version of the noun:

• zoo, zoos; loo, loos; moo, moos; studio, studios; duo, duos.

If a consonant comes before an –o ending, a plural is formed by adding –es to the singular version of the noun:

• tomato, tomatoes; potato, potatoes; zero, zeroes; hero, heroes.

For common nouns ending in –f, a plural is usually formed by replacing –f with –v and adding es:

• leaf, leaves; self, selves; elf, elves;

• exceptions: reef, reefs; cliff, cliffs; cuff, cuffs

For numerical figures, add an s, no apostrophe:

• 1700s, 1820s, 1940s, 1950s, 1960s

For endings of commonly used Latin words:
Words ending in –a, add es:

• alumna; alumnae

• exceptions: formula, formulas

Words ending in –us, change to i

• alumnus, alumni

Words ending in –um, add s:

• dictum, dictums; podium, podiums; stadium, stadiums;

• exceptions to this rule usually keep the original Latin plural ending(a): agendum, agenda; curriculum, curricula; medium, media.

Words ending in –i, add s:

• alibi; alibis.

Ifs or if’s?
Just as numerical figures add an –s without an apostrophe, so too do words used to convey a general number:

• if, ifs; but, buts; and, ands.

For accepted abbreviations and multiple letters:

• IOU, IOUs; IQ, IQs; VIP, VIPs.

These nouns change form to indicate the plural:

• man, men; woman, women; foot, feet; mouse, mice; goose, geese; louse, lice; child, children; tooth, teeth.

These nouns stay the same in the singular and the plural:

• sheep; moose; deer; steer; chassis.

Don’t confuse these singular nouns as plurals:

• news; measles; grits; scissors; pliers.

Grammar is always a bit overwhelming, even for writers, and can be boring to boot. Hopefully this layout makes reading a bit easier for you. Also, check the excellent book Eats, Shoots & Leaves by Lynn Truss. It is what a grammar book should be: easy to read, wittily presented, and not at all boring.

Public Domain webisites like Project Gutenberg and Bartleby.com are gold mines if you’re looking for free literature or verse, style and grammar guides, and more.  They provide a plethora of work pre-1920’s, and its all free for you to devour at your pleasure.

Project Gutenberg offers 18,000 books online. These include everything from books by Ovid and Dante to Jane Austen, Mark Twain, and numerous other authors. They are an excellent resource, and all the books can be downloaded as e-books.

Bartleby.com is an open resource, Public Domain site that offers numerous writing and grammar resources, including the American Heritage Dictionary, Strunk & White,  Bartlett’s Familiar Quotations, and even Gray’s Anatomy. Their searches are divided into reference, verse, fiction, and non-fiction.

In short: don’t write “something”. Write “something.”

While this sounds nitpicky, it shows a lack of proofreading, the ultimate sign of carelessness in a professional document.

Common mistakes like this imply several things:

a) the writer doesn’t know or can’t remember their grammar.
b) the writer forgot to proofread.
c) the writer doesn’t care.

Whether you’re a writer or not, it is your responsibility to your readers to present clean, error-free material. If you don’t proofread, that implies laziness. And while lazy writing is bad enough, not caring is worse. Now some might say “well, most people aren’t that observant, so it doesn’t matter anyways.” Perhaps. But not caring does suggest a lack of respect for your own work that isn’t lost on your readers. Never underestimate your reader or client. If they’re going to read or buy something from you, they want a product or service that inspires the most confidence.

After all, if you don’t care about your work, why should they?

Luckily, there is an easy solution to bad grammar: repetitive proofreading. For most people, once is not enough. Lather, rinse and repeat. In addition, have at least two other people proof your work for you.