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Bush held a news conference at the White House on Thursday, following the completion in July of the withdrawal of 5 extra combat brigades that had been deployed in Iraq last year.

Is following a preposition or a participle?
In my opinion, both interpretations are possible whether or not the existance of a comma before following.
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Liveinjapanboth interpretations are possible
Yes. The terms 'participle' and 'gerund' specify forms derived from verbs. In my opinion, they are not parts of speech. So a word can be both a participle and a preposition at the same time. You do not have to think that it can be only one or the other. If asked for a 'part of speech', I would say the word following in your example is a preposition. It acts like after.
After the completion of his act, the clown left the stage.
Following the completion of his act, the clown left the stage.

CJ
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Liveinjapan
CalifJimSo a word can be both a participle and a preposition at the same time.
Thanks so much, CJ.

Understand! I add my thanks too, CJ. It's the first time I've "heard" anyone say this. Most posters seem to imply such thoughts are verboten.

How about a participle and a gerund at the same time??

- A.
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Comments  
CalifJimSo a word can be both a participle and a preposition at the same time.
Thanks so much, CJ.
Understand!
 Avangi's reply was promoted to an answer.
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