As you can imagine, we see thousands of documents weekly at ProofreadNOW. We're cataloging a huge collection of contextual errors as we solve more and more problems for our clients.
Common errors abound, and one wonders why Microsoft Word in all its limited glory has not addressed many of these standards. For your reading and editing pleasure, and more important, for the good of your next document, we offer here a few standards to refer to when it comes to using letters, abbreviations, numerals, noun coinages, etc.
Letters, abbreviations, and numerals. Capital letters used as words, abbreviations that contain no interior periods, and numerals used as nouns form the plural by adding s.
- the three Rs
- the 1990s
- IRAs for retirement
- vol., vols.
- ed., eds.
- p. (page), pp. (pages)
- n. (note), nn. (notes)
- MS (manuscript), MSS (manuscripts)
Use of apostrophe. To avoid confusion, lowercase letters and abbreviations with two or more interior periods or with both capital and lowercase letters form the plural with an apostrophe and an s.
- x's and y's
- M.A.'s and Ph.D.'s (or MAs and PhD's)
Words in quotation marks. The plural of a word or phrase in quotation marks may be formed by the addition of an apostrophe before the s, with the closing quotation marks following the s (though rewording is usually a better option). A plural ending should never follow closing quotation marks.
- How many more "To be continued's" can we expect? (not "To be continued"s)
Noun coinages. Words and hyphenated phrases that are not nouns but are used as nouns form the plural by adding s or es. To avoid an awkward appearance, an adjustment in spelling (or sometimes an apostrophe) may be needed.
- ifs, ands, or buts
- dos and don'ts
- threes and fours
- yesses and noes (or yes's and no's, especially if maybe's is also used)
Source: Chicago Manual of Style, 15th edition