Student or Learner
I see that the comma is omited in the following case:
We Americans/Canadians decided not to...
We, Americans/Canadians, decided not to...
I thought that the commas would be necessary as it is a form of using "Americans/Canadians" as an appositive.
What is the comma rule on this one?
Thank you for finding out what the rule is. However, the explaination could be different and better.
"EX: My brother, Charles, is a neurosurgeon. (Nonrestrictive)
EX: My brother Charles is a neurosurgeon. (Restrictive)
Notice that in both cases the word Charles is the appositive. However, the fact that the sentences are punctuated differently indicates two different meanings. The first sentence signifies to the reader that Charles is simply renaming the noun brother. Therefore, the information is not essential to the meaning of the sentence, so it may be set off with commas. In other words, we can safely make the assumption that the writer has only one brother and his name is Charles. This is why the information is not essential to meaning in the sentence.
However, in the second example the word Charles, although it is acting as an appositive, is not set off with commas, which therefore indicates to the reader that Charles is not simply renaming the word brother – it is supplying additional information in the form of identifying which brother the appositive is referring to. In this case, the speaker has more than one brother, so the information is restrictive and is not set off with commas."