Rebecca,
     You answer the question yourself:

And quite naturally, we readily, and easily know that
"John is happy and well rested this fine afternoon."

The "John is" in your example is not incomplete ― except for you linguists. My student would immediately resort to, as you note, the natural and ready "John is happy and well-rested." I have never EVER seen a student simply write "John is" out of  a meaningful context. As a result, there is no need to "teach" students that "John is" requires a complement. I think you have given me another example of what linguists are interested in and want to teach, but what most of us comp teachers simply think is irrelevant. 
Ed


>>> "rebecca s. wheeler" <[log in to unmask]> 03/23 2:12 PM >>>
Ed Vavra writes:

>      What we are dealing with, I think, is a fundamental different in the
>way linguists look at language and the way the rest of us do. Linguists
>see "John is" as an incomplete pattern and thus want to SHOW that it needs
>a "complement." But if we teach grammar/syntax in conjunction with
>student's writing and reading, it would be EXTREMELY rare for a student to
>run across the 'sentence' "John is." Thus, from the students' perspective,
>I suggest that the whole question is irrelevant.
>Ed V.

What about an environment like the following:

It had been a hard day. I got home to find that my dog had turned over the
flowerpot and had drug the dirt and plant all over the dining room. This
puppy had found the bag of potatoes and had lovingly chewed each one,
partially, over the course of the apartment. The trash was strewn
everywhere, and to top it all off, Kiku STOOD atop the dining table.  When
I hollered, he, in fear, relieved himself.  It was all too much. Not
trusting myself to handle the situation, I called to my incoming
housemates, "Who's happy and well-rested this fine afternoon? I got a
situation here!" And a companion answers, "John is."

I'd say that's not only an instance, but a very common instance in which a
student could run across the sentence, 'John is."  Indeed, in the discourse
context, in order to make sense of the utterance, we naturally look back to
the previous sentence to "complete" the interpretation. So in some sense,
the 'sentence' "John is" is indeed "incomplete", in that upon encountering
it, we look for something else to plunk in that next spot the sentence in
our understanding. And quite naturally, we readily, and easily know that
"John is happy and well rested this fine afternoon."

Sometimes fragments are pernicious and sometimes they're not. The times
they're pernicious are when the reader can't figure out what is going on,
what the intended meaning is.  This example, though I wouldn't actually
call it a fragment (it is more like "John is ______" and then we naturally
fill in that blank with the adjectival/descriptive info that came eralier),
is utterly natural, and in no way pernicious. So, possibly, some of the
sentence pattern info  might be useful to students, in examples such as
these, to distinguish (among vastly many other things) between fragments
that don't work, and ones that do.

Reminds me of an example in the linguistics lore:

In isolation, the following seems 'ungrammatical': "Regan thinks scrambled."
But as an answer to the question, "How does Kissinger like his eggs?",
"Regan thinks (that Kissinger likes them) scrambled" makes perfectly good
sense.

Surrounding discourse context is indeed crucial.


by the way, the dog story is true.

cheers,

rebecca

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Rebecca S. Wheeler, Ph.D.               office phone:  801-626-6009
Department of English                   office fax:      801-626-7760
1201 University Circle
Weber State University
Ogden, UTah 84408-1201
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