I'm going to come down on the side of the adverbial.  You might call it
ambiguous, I suppose, just as "I have a pain in my back" could be either,
"In my back I have a pain" or "I have a back pain."  In either case,
however, the "back" structure tells where the pain is.

A more clear-cut kind of ambiguity appears when the prepositional phrase
tells either "which" or "where."  For example, "We followed the man in the
park" or "We talked to the man in the car."

You can often test for adverbialness by moving the phrase away from its
noun.  If you can do so without changing the meaning, it's probably
adverbial.

On the question of the verb, I see no ambiguity at all.  "Have" is a
transitive verb (not a form of be, Donna!), not linking.  And in the case
of "The migraine is in her head," "be" can take an adverbial as well as a
subject complement.  The pain is in her foot, The book is in the library,
My mother is in the hospital, The play was yesterday.  Those structures
following "be" are adverbial, not adjectival.  You might want to call them
complements, in that they "complete" the predicate--but they're not
adjectival.

Martha Kolln



>The foot-migraine sentence (Sally has a migraine in her foot) is ambiguous:
>
>*  If it answers the question, "In what organ does Sally have a migraine?," the
>prepositional phrase is adverbial.  She has it in her foot.
>
>*  If it answers the question, "What ailment does Sally have?," the
>prepositional phrase modifies the noun "migraine."  It's a migraine in her
>foot.
>
>By the way, is this a medical condition of which I was not previously aware?
>
>Dick Veit
>
>Richard Henry wrote:
>
>> Hi,
>>
>> Here's a sentence my class in American English Grammar has been kicking
>> about:
>>
>>    Sally has a migraine in her foot.
>>
>> The questions have swirled around the function of "has", the role of the
>> noun phrase "a migraine" and the role of "in her foot" in the sentence.
>> Complications have invoked the indefinite article and the possessive
>> pronoun.
>>
>> 1.  Is "in her foot" functioning as an adverbial modifying has? or as an
>> adjective modifying migraine?
>> Initial arguments opted for adverb because the phrase clearly answers where
>> the "having" is.
>> However, we've also considered the following:
>>     Sally has a migraine.
>>     The migraine is in her foot.
>>     Sally has a migraine THAT is in her foot.
>>     Sally has a migraine in her foot.
>> This suggests the prepositional phrase is functioning as an adjective.
>> One student has (albeit cautiously) suggested that the phrase 'in her foot'
>> is close to 'of her foot' or 'of the foot' -- i.e. that we have a genetive
>> construction: Sally has a foot migraine.
>>
>> 2. Is "has" in this case functioning as a linking or as a transitive verb?
>> Those arguing for transitive make a powerful case for 'a migraine' as a
>> direct object.
>> However, the counter-argument suggests that a migraine is an attribute of
>> Sally, in a way that a shoe is not.  So 'Sally has a shoe on her foot'
>> would be a transitive (with 'on her foot' functioning as an adverb....)
>>
>> We were on our way to complicating the matter with the addition of the
>> clause: 'which is all in her mind.'
>>     Sally has a migraine in her foot which is all in her mind.
>>
>> Thanks,
>>
>> Rick Henry
>> SUNY Potsdam