The rules governing the use of the letter sign may be summarized as follows:
Use the Letter Sign
- With all single letters that mean letters, not words. [Class B]
- With single letters followed by 's. [p's and q's]
- With letters that represent shapes. [a Ved formation]
- With single letters joined to words by a hyphen or dash. [x-ray]
- With single letters joined to other single letters by a hyphen or dash. [a-j A-J]
- With single enclosed letters in regular text (drop enclosure symbols). [(a) "b"]
- With unpunctuated letters in outlines and lists.
- With names, words, or letter groupings that could be mistaken for short-form
- With any single letter connected to a number by a hyphen. [c-4 4-C]
- With a letter or letter grouping immediately following a number, or following a
number and a hyphen. [6MG 6-mg]
- With letter groupings joined to a number by a hyphen that could be mistaken for a
short-form word. [Fr-10 6-ab]
- With lowercase roman numerals and foreign ordinal numbers (to be studied in
Do Not Use the Letter Sign
- With the words a, I, and O.
- With letters that are followed or preceded by an apostrophe, hyphen, or dash indicating
omitted letters. [Fish 'n' Chips d--n]
- With letters designating topics in outlines or listings if they are followed by or
enclosed in punctuation.
- With letter groupings that could not be mistaken for a short-form word. [XYZ]
- With words, names, or letter groupings that correspond to short-form words, but, because
of context, could not be mistaken for one.
- With a contraction that immediately follows a number, as in ordinal numbers. [1st 4th]
- With any letter that is immediately followed by a number. [M6]
- With letter groupings followed immediately by a number, or by a hyphen and a number,
that will not be confused with a short-form word. [TY60 ty-60]
- With words following a number and a hyphen, unless all of the letters of the word could
be misread as a number. [6-pack]
- In stammered words (see 12.7.a). [b-b-boy]
- With initials and abbreviations followed by periods or a slash (to be studied later).
Try the Drill in WESBraille.