Suggestion: Markup for an incorrect example

Question

Can we have markup for example sentences, as distinct from actual quotes? And markup to distinguish a correct example from an incorrect one? (Strikethrough is a poor substitute.)

Answer 1

The standard practice in linguistics is to distinguish a text being discussed from the actual discussion by putting it in italics:

To be or not to be is a conjunction of infinitives acting as an NP.

When a lengthy text is under discussion it is distinguished by setting it as an indented paragraph, without italics, like long quotations in ordinary academic texts.

The limited Markdown syntax made available on SE does not permit us to follow standard linguistic notation for example sentences, like this (from Declerck and Reed, Conditionals: A Comprehensive Empirical Analysis, 2001):

Aside from the numbering and indentation, I usually follow the use illustrated here, with the example text set normally (marked up as occasion demands and Markdown permits) and my own comment in italics. But that is not a universal practice; CGEL, for instance, does just the opposite, setting the example in italics and their own comment in ordinary type.

Standard practice for quoted texts in all disciplines is to give a source at the first citation; the absence of a source may be taken to signify that the text is the author's own invention.

The most common marker for a grammatically or semantically unacceptable utterance is a leading asterisk, as in CGEL's 7.ii.a., above; this may be placed before the utterance as a whole or before a specific unacceptable word or phrase.

^∗ This utterance are unacceptable.
This utterance ^∗are unacceptable.
This utterance {is /^∗are} unacceptable.

Some linguists use # instead of the asterisk, and often one or more ? are used to mark various degrees of unacceptability.

Here on ELL I have taken to marking an acceptable utterance with ^ok when it contrasts with unacceptable utterances (which is also why I space a leading asterisk, so the examples will line up better); but that's my own affectation, not a generally observed practice.

^∗ This utterance are unacceptable.
^okThis utterance is acceptable.

<sup>&lowast; </sup>This utterance are unacceptable.  
<sup>ok</sup>This utterance is acceptable.

Answer 2

I sometimes use images, such as

• Correct example here:
• incorrect example here.

This practice is very common in the Wikipedia manual of style (MOS) pages. Remember that any markup should produce a simple and clear effect for readers who are learners.