Adjective or Adverb?

I got into a lengthy and heated debate with my old college chum last night and just wanted to smite him. Apart from the fact that he called Don Gauger a liar, there's this business of prepositional phrases that so flummoxed him. Let's see if I can set him straight once and for all.

This all began when we got into one of our usual discussions on the vagaries of language. What started it all was the following joke:

Did you hear about the man with French asthma? He could only catch his breath in snatches!

Of course, the humor lies in the fact that the response may be parsed in two distinct ways. But what caught my attention more specifically in our dialectic last night was that what looks like a prepositional phrase is in fact acting as either an adjective or an adverb, depending on the interpretation. This rather surprised me so I had to look it up on the Web and see what professional grammarians have to say about it.  Here's what Elizabeth O'Brien reports:

"Prepositional phrases act as single parts of speech. This seems sort of funny, but all of the words come together to act as one part of speech. Each word within the phrase has its own job, but the words also work together to perform one job."

O'Brien then goes on to diagram some sentences in traditional grammar (like we all did in grade school) to show that they may act as either adjectives or adverbs, as I suspected. My key point is the same as hers: form is not function. While the form (analyzed strictly according to the particles making up the phrase) appears to be prepositional in nature, its function (taken as an indivisible unit) is not.

Applied to the joke, then, if "in snatches" is taken as an adjective, it modifies the direct object "his breath" by answering the question, "Where?"

But seen as an adverb, "in snatches" modifies the verb "catch" and answers the question "How?" It is roughly equivalent to saying he catches his breath spasmodically, haltingly, convulsively, jerkily,...all adverbs.

O'Brien's traditional grammar approach is good, but consider this from a Noam Chomsky slant, via transformational grammar. In Chomsky's scheme, the grammar "occurs" as a thought goes through a nexus of transformations, concluding with a complete sentence.

But here's my point. The two starting thoughts are completely different: the chap catching his breath in a snatch (a place), or catching his breath asthmatically (a manner).

And yet, from a particle point of view, the two distinct thoughts generate exactly the same sentence.

Now that is a curious phenomenon, don't you think?

Next essay: Editing Oscar