Is there certain rule to discern which modifies noun which modifies verb?

Question

  Harry's heart gave a horrible jolt. A test? In front of the whole school? But he didn't know any magic yet –– what on earth would he have to do? He hadn't expected something like this the moment they arrived. He looked around anxiously and saw that everyone else looked terrified, too. No one was talking much except Hermione Granger, who was whispering very fast about all the spells she'd learned and wondering which one she'd need. Harry tried hard not to listen to her. He'd never been more nervous, never, not even when he'd had to take a school report [i] home to the Dursleys saying that he'd somehow turned his teacher's wig blue. He kept his eyes fixed on the door. Any second now, Professor McGonagall would come back and lead him to his doom.

  Then something happened that made him jump about a foot in the air - several people [ii] behind him screamed.

(Harry Potter and the Sorcerer’s Stone, by J.K.Rowling)

The best part is that the owner shares the same passion as the customers when it comes to buying parts [iii] for their cars. (pristineparts.com)

My own language using different suffixes for modifying noun, or adverb, verb or the sentence, when I come across [i]~[iii], it’s not easy to decide either these modify the previous noun phrase or they behave like adverb (or adjunct) to modify verb (or sentence, clause?). Can they be discerned either way, or are they ambivalent? Is it only dependent on, who the reader is, when a person reads?

Answer 1

A locative or preposition phrase immediately following a noun is usually taken as a restrictive modifier on the noun, if the semantics permit.

I have no hesitation in describing your [ii] and [iii] as modifiers on the preceding nouns. Which people screamed? —the people behind him. What kind of parts do they buy? —parts for their cars.

• But in a different sytactic location or a different semantic context, the same phrases would be taken to modify the verb or the clause:

  People screamed behind him. —the position compels an understanding of behind him as the origin of the screaming.

  Just as customers have a passion for buying toys for their children, they have a passion for buying parts for their cars. —the parallelism compels an understanding of for their cars as designating the beneficiary of the purchase.

But in [i], as jimsug says, the locative home is an “object” of take. I would call it an object complement, which as you already know means it ‘modifies’ report while being syntactically dependent on take.

In other circumstances, however, the semantics of an adjunct may prohibit ascribing it to an immediately preceding noun:

Prof. Sartorius read your letter with great pleasure.
He accepted our proposal on one condition.

There are, however, ‘borderline’ situations:

Prof. Sartorius read your letter in the British Library.

Does in the British Library tell us where he read the letter or which letter he read?

In these cases we must look to the broader semantic context. It is unlikely that a letter by you, Listenever, forms a part of the BL's collections, so the default reading here would be that Prof. Sartorius was in the BL when he read your letter.

But what about these?

1) Prof. Sartorius read Dickens’ letter in the British Library.
2) Prof. Sartorius read the copy of Dickens’ letter in the British Library.

Here I suggest, as rule of thumb, that we take the prepositional phrase to modify the noun only if it is understood as restrictive.

• 1) There are many letters by Dickens in the BL, so although a specific letter is probably intended, it is very unlikely that in the British Library is intended to distinguish this letter by Dickens from others are elsewhere. The ‘default’ reading is that in the British Library modifies read: “It was in the British Library that Prof. Sartorius read Dickens’ letter.”

• 2) While the BL probably has copies of many letters by Dickens, the copy implies a specific copy, making it far more likely that in the BL is intended to designate which copy Prof. Sartorius read. The ‘default’ reading is that in the British Library modifies copy: “It was the copy of Dickens’ letter in the British Library that Prof. Sartorius read.”

In both cases, however, these are ‘default’ readings: they are implicatures, which may be cancelled by further context:

1a) Prof. Sartorius read Dickens’ letter in the British Library, but did not read his letter on the same topic in the V&A.

2a) Prof. Sartorius read the copy of Dickens’ letter in the British Library, where he had taken it order to compare it to the original.

Answer 2

he'd had to take a school report home to the Dursleys

Clause analysis:

• Subject: he
• Verb (Phrase): had had to take
• Object: a school report
• Object: home
• Adjunct: to the Dursleys

home

This can only be an object for the verb take. It cannot, as you suggest above, port-modify the noun phrase a school report, unless it is a school report home: a place where school reports live. This is possible, but incredibly unlikely.

several people behind him screamed

• Subject: several people or several people behind him
• Verb (Phrase): screamed
• Adjunct/circumstance: (behind him)

behind him

This is an interesting case - because of its location, the clause might have either:

• the noun phrase several people behind him
  Indicating that the several people who screamed were behind Harry.
• the noun phrase several people and the adjunct to the sentence behind him Indicating that several people screamed behind Harry.

As you can see, there's essentially no difference in meaning. I highly doubt that people could scream behind Harry if they aren't behind him. This might be an unusual case, though, and in this instance it doesn't matter whether the prepositional phrase modifies the entire clause, or just the noun phrase.

buying parts for their (the customers') cars

• Subject: None - this is a non-finite clause, as you can see with the non-finite verb
• Verb (Phrase): buying
• Adjunct/circumstance: (this is a circumstance of reason) for their (the customers') cars

for their (the customers') cars

This prepositional phrase can only modify the verb buying.

However, there's the possibility that it actually modifies the matrix clause:

The best part is that the owner shares the same passion as the customers (when it comes to buying parts) for their cars.

Unfortunately, there's no way to tell without being able to question the author.