Benjamin Clayborne
Auror
I do not dispute that there are many other uses for commas, but what I stand is entirely true.
If you separate two clauses with a conjunction, you only use a comma if both clauses are independent.
S1. Correct - This clause is independent, and this clause is independent.
S2. Correct - This clause is independent but not this one.
S3. Incorrect - This clause is independent, but not this one.
I see a tonal difference between S2 and S3. To me, the S3 is more urgent than S2, but I wouldn't consider it wrong. I know it wouldn't bother me if I saw S3 while reading. That comma, to me, implies a pause, but I'm not sure what's "incorrect" about it. Does it make the sentence harder to understand? Is it confusing? Will a majority of readers stumble over it or be bothered by it? If not, then I'm not sure what the problem is with using it.
Actually, now S2 bothers me, because:
S4: This clause is independent but not purple.
S2: This clause is independent but not this one.
S4 makes sense, but replace "purple" with "this one" and now it reads weird to me.
Also, if you're going to state flat-out that something is incorrect in a language that has no central defining authority, it would probably help if you cited which particular grammatical authority you're using the rules from.

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