Dear teachers,

A/ 1) Can we use punctuation signals within dashes? e.g.
“I have always been fond of reading this comes from my mother ; /, she was a storyteller.”

2) Or should the information written between dashes be formed of a single clause only? e.g. “I have always been fond of reading this comes from my mother who was a storyteller.”

B/ How should I spell the following ?
“literature” takes one “t” in English, but two “t’s” / “ts” (?) in French.”

Thank you,
I'd say you may have commas between dashes:

13. The four greatest names in English literature are almost the
first we come to,--Chaucer, Spenser, Shakespeare, and
.--B. (Omit the comma before the dash)

H.W. Fowler, The King's English, 2nd ed. 1908.
I'd agree with MM on the clutter quotient.

In example A, the part after the dash seems like an aside, so it might do better in parentheses.

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A is an interesting one, Hela. Dashes are presumably casual colons, and I find the same problem with both of them. If it looks too awkward or unclear, I recast as an unpunctuated clause.

B-- This is one of the special cases in which you are permitted to use an apostrophe to make a plural; it seems evident that ts would be taken at face value otherwise (as in tsetse fly). Personally, I would say the t is doubled in French, and avoid the awkward formation.
That's a very good advice, Mr Micawber! Emotion: big smile
 Marius Hancu's reply was promoted to an answer.
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 MrPedantic's reply was promoted to an answer.