How to discern different phrases, signs to observe?

Question

“Snapping shut his mobile, Dalgliesh reflected that murder, a unique crime for which no reparation is ever possible, imposes it own compulsions as well as it's conventions. He doubted whether Macklefield [the murder victim's Will attorney] would have interrupted his country weekend for a less sensational crime. As a young officer he, too, had been touched, if unwillingly and temporarily, by the power of murder to attract even while it appalled and repelled. He had watched how people involved as innocent bystanders, provided they were unburdened by grief or suspicion, were engrossed by homicide, drawn inexorably to the place where the crime had occurred in fascinated disbelief. The crowd and the media who served them had not yet congregated outside the wrought-iron gates of the Manor. But they would come, and he doubted whether Chandler-Powell's [owner of the Manor where the murder was committed] private security team would be able to do more than inconvenience them.” ― P.D. James, The Private Patient

In this, I aim to discern these phrases. a unique crime for which no reparation is ever possible I think I discern an appositive. I discern it thinking it seems to maybe add information to what came formerly, a noun, murder? That seems a sign I may utilize.

In As a young officer he I may not get how to discern that. It seems maybe a dependent phrase. May you aim to observe heads (I may not seem to get what that signifies in grammar), and or maybe a first word?

I may not get if unwillingly and temporarily, provided they were unburied by grief or suspicion, and But they would come, and he doubted whether Chandler-Powell's [owner of the Manor where the murder was committed] private security team would be able to do more than inconvenience them.

But they would come, and he doubted whether Chandler-Powell's [owner of the Manor where the murder was committed] private security team would be able to do more than inconvenience them. seems to get me. In But they would come, they seems a subject here, a subject of would, transitive, and object come? They would come. Or come, intransitive, They come, would maybe like auxiliary They would come? I guess I may not get why But they would come follows a comma?

Answer 1

Yes, that first one is an appositive. It's describing murder.

You're splitting the sentence up wrong on the second one. Here's the sentence:

As a young officer he (too) had been touched (if unwillingly and temporarily) by the power of murder (to attract even while it appalled and repelled).

So the stripped down version of that sentence is:

As a young officer he had been touched by the power of murder.

So "too" is just referring to the fact that he's not the only one that's affected in this way. "If unwillingly and temporarily" is describing the way in which he was touched. He didn't choose to be touched by murder crime scenes, that just comes with being a police officer. He's also saying that the way in which he has been affected is not permanent. "To attract even while it appalled an repelled" is giving you more detail on exactly what the power of murder that is being referred to is. It is the power to attract while at the same time repelling. It's interesting, but also horrifying.

Third one:

He had watched how people involved as innocent bystanders, provided they were unburdened by grief or suspicion, were engrossed by homicide, drawn inexorably to the place where the crime had occurred in fascinated disbelief.

This means that the following statements don't apply to bystanders who are burdened by grief or suspicion. In other words, people not involved in the murder are drawn to it, but people who might have committed the murder or who might be suspicious of who did react differently.

Fourth one:

The crowd and the media who served them had not yet congregated outside the wrought-iron gates of the Manor. But they would come, and he doubted whether Chandler-Powell's [owner of the Manor where the murder was committed] private security team would be able to do more than inconvenience them.

I've included the previous sentence, as it's closely related to this thought. I may have even hooked all three of these together as one long complex sentence, myself.

The 'they' here are the "crowd and media" mentioned in the previous sentence. They are the bystanders drawn by fascinated disbelief mentioned earlier in the paragraph.

"Would come" is a verb phrase. As he's just stated with "had not yet congregated", these bystanders aren't here yet. However, he's confident that they will come. The contrast between them not being here yet, but definitely arriving in the future, is the reason for using the word 'but' as a contraction between sentences.

This paragraph is mostly about the psychological effect of murders and murder scenes on people, and the fact that they will definitely come is part of that effect.

The next independent clause follows an 'and'. He's saying that the crowd will be able to satisfy their fascination because the security forces won't be able to keep them away from "the place where the crime had occurred".

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I don't really know any quick tips to help you figure these out. One thing that might help, if you're not already doing it, is to try removing sections surrounded by commas to see if the remaining sentence makes more sense. For instance, in the first one, you though that everything before the 'too' was a single unit, when really the 'too' was in the middle of "As a young officer he had been touched".