If you're talking about a particular letter of the alphabet, how do you format it? Do you just write it? Do you put quotes around it? Do you italicize it? Do you just have to write it out?
Does the h come before the g or after it?
Does the 'h' come before the 'g' or after it?
Does the h come before the g or after it?
Does the aitch come before the gee or after it?
Which of those would be right? Any of them?
In formal writing which preserves the use–mention distinction and has access to both roman and italic faces, your third choice is the preferred rendering:
Does the h come before the g or after it?
For example, in the OED’s entry for the letter g, they write:
From the 13th c., however, the ȝ was by some scribes wholly or partially discarded for y or gh; a few texts have yh. In the 15th c. vocabularies the words beginning with ȝ are at the end of the alphabet. Caxton uses the symbol sparingly, chiefly before final t. The English printers of the 16th c. scarcely use it at all; but in Scotland it survived longer, and has left a trace in the use of z for y in the spelling of surnames like Menzies and Dalziel, and of such words as capercailzie, gaberlunzie.
However they do then go on to write this, in which a mixture of casing and font changes is employed:
In modern English G has the so-called ‘hard’ sound [g] at the end of a word, before a consonant or a, o, u, (exc. in gaol, gaoler), and in words of Teutonic etymology before e and i, as in give, get; also in Hebrew proper names, as Gedaliah, Gideon. In words from Lat. or Romanic it has the ‘soft’ sound [dʒ] before e, i, y; and at the end of a syllable, in words of whatever origin, the sound [dʒ] is represented always by dge or ge, the letter J not being used in this position.
According to the Chicago Manual of Style, individual letters and combinations of letters of the Latin alphabet used as letters are usually italicized.
Examples:
the letter q
I need a word with two e's and three s's.
Just be careful of the context. Never use italics to indicate a letter in scientific texts or any context where people could think the letters have some scientific meaning. In science (and maths), italicised letters indicate that they represent variables.
For example t is just the letter t (maybe a sample label) but when you see t, you know its time. Same with T (temperature). And x could be the letter x ("x marks the spot") or a multiplication symbol, but x is a variable, as in y=3x+2 or the x value on a graph.
For example, see:
https://www.shearsoneditorial.com/2012/07/typographical-conventions-for-mathematics/
