Non-restrictive
(of a relative clause or descriptive phrase) giving additional information about a noun phrase whose particular reference has already been specified.
I read that a restrictive word phrase or clause "limits" meaning, because it is not inessential. I get this. Is that "limit" always of the meaning of the word just before it, never a word before that or after itself?
An example of it doing so would be the following:
My sister Susan went to the shop.
'Susan' limits the meaning of my 'sister', because I am expressing that it is not just any sister, but Susan. The non restrictive version would be:
My sister, Susan, went to the shop.
Two follow on questions:
Can every restrictive word phrase and clause be made non-restrictive by the addition of a parenthetical comma, and vice versa by deleting parentheses.
And is every parenthetical element non restrictive?