Hi New2grammar
What I was trying to describe is connected with a single choice among things in a clearly named group of things. As an illustration of what I'm talking about, I don't really feel comfortable with your sentence as it is worded.
1- Before the Bali bombings, there wasn't a single sign of impending disaster.
2- Before the Bali bombings, there wasn't any sign of impending disaster.
3- Before the Bali bombings, there was no sign of impending disaster.
The first three sentences emphasize the idea of
one (in this case, not even one).
4- Before the Bali bombings, there weren't any signs of impending disaster.
5- Before the Bali bombings, there were no signs of impending disaster.
Sentences 4 and 5 focus more generally on the idea of
zero or none. Sentences 4 and 5 suggest that one or more signs could have been possible, but none of these possibilities happened.
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Here is another example of what I mean by "it doesn't matter which one" when using
'any' + a singular noun:
Q:
Who should I ask to find out how to build the passive form of the present perfect?A:
You can ask any English teacher. (In other words, it doesn't matter which
one you ask -- and asking one randomly chosen English teacher is enough because all of them will be able to answer your question.)