I notice that "let alone" is used in sentences that have a comma. The structure of the sentence is what comes before the comma is some kind of negative statement. Right after the comma is "let alone," followed by the rest of the sentence.
What does "let alone" mean here? Does it mean the same thing as "or even?" Can someone explain this phrase and sentences that have it?
It is roughly synonymous with the terms "not to mention" or "to say nothing of", except that those terms require a change in tense for the following action.
The sentence "I wouldn't go near a stingray, let alone pet one" implies that the speaker would stop far short of even being in a situation to do what follows the "let alone" clause. They wouldn't go near a stingray, therefore it is out of the question that they would pet one.
in contrast to
The first part of the sentence sets up the situation, then what follows the comma, prefaced by "let alone" shows what a reasonable person might expect in contrast to the lesser option.
