The recent digression of the Ghostbusters thread into the nuances of punctuation brought to mind one of my pet punctuation peeves (notice how nicely that alliterates -- thank you). And I just encountered a perfect example of MISuse, in an article about Maria Sharapova and her doping admission.
The basic rule is, when commas are used to set off a subservient clause, the primary sentence should read correctly if the clause is removed.
Sharapova has dropped to No. 7 in the WTA rankings, and due to injuries, she has played just three tournaments and the Fed Cup final in the last eight months since Wimbledon.
That's the way it appears in the article. It's wrong -- and that's the way most writers today use it. I see it so often that I have to be constantly alert to catch myself when (not if) I do it.
If we remove the clause from the sentence above, we're left with the following:
"Sharapova has dropped to No. 7 in the WTA rankings she has played just three tournaments and the Fed Cup final in the last eight months since Wimbledon."
Which makes no sense. It's not one sentence, it's two sentences, without benefit of a period as a separator. But, move the leading comma just one word to the right and we get ...
"Sharapova has dropped to No. 7 in the WTA rankings and,
due to injuries, she has played just three tournaments and the Fed Cup final in the last eight months since Wimbledon."
Now if we remove the clause we are left with a sentence that remains a proper sentence:
"Sharapova has dropped to No. 7 in the WTA rankings and she has played just three tournaments and the Fed Cup final in the last eight months since Wimbledon."
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