Could you help me how I figure it out?

Jamie wants to obtain his backupsupport and says to the old man, "I'll bring you back more diamonds than you can count."

I don't understand this parenthesisquoted part.

I think "study" means like ""to stare"."

Stare is simply looking at them intensely. Study means you are looking at them in order to understand them, kind of like observing or reading a person.

Doe the "for" mean time interval like "for two hours"?

Yes! In this sentence it's "for an eternity."

In other words, could I say, ¶
"The old man silently studied him while Jamie. This feelst like an eternity"?? to Jaime"

The complicated part about this sentence is that they've basically combined two ideas into one sentence.

The first idea is that the old man silently studied him for an [x amount of time].
The second idea is that this [x amount of time] is so long that it felt like an eternity for Jaime.

Hope this makes sense!

It would be a big help if you could check and advise me.

A difficult pPhrase to mFor Me 2

I'm was reading a novel, and came across a difficult phrase for me to read.

Could you help me how I figure it out?

Rumor has it that the old man backsupports diggers of diamonds.

Jamie wants to obtain his backupsupport, and says to the old man, "I'll bring you back more diamonds than you can count."

Is this correct?

Hmmm, it's very close for sure. When you "study" someone, you take a long look at them, observing any noticeable characteristics or mannerisms of the person. To me, it seems that the old man is trying to tell how serious Jamie is, and "studies" him to notice how strong his conviction is.

Does the "for" mean time interval like "for two hours"?

Yep!

Otherwise, does it indicate reason, like the phrase "because of"??

In other words, could I say, ¶
"The old man silently studied him while Jamie feels like eternity"??

Not necessarily. Saying it like this presents 2 issues;
1) This implies that Jamie is doing something else simultaneously (「お爺さんがジェーミに じっと見てジェーミの遠近法から、永遠を掛かったんだ」の代わりに「お爺さんがジェーミにじっと見るの間に、ジエーミは永久みたいと思った。」
2) That "eternity" is a person, and that Jamie feels similar to that being

It would be a big help if you could check and advise me.

A difficult phrase tofor me 2

"For" vs "to" feels like a pretty subtle distinction, but "to" wouldn't be used here. In this kind of sentence, "to" tends to have a more subjective feeling.

> He is like a father to me
> (Someone says they're struggling with a math problem.) What's the issue? This seems like a pretty simple problem to me.

"for" feels a little more objective, practical, and if the sentence were to continue, "to" may also appear.

> He has acted like a father for me ("for" as in 私のため)
> This is a hard problem for me to solve. (though "to solve" is often omitted)

Could you help me how I figure it out?

If I were to translate

> どう理解したらいいか教えていただけないでしょうか

I think I'd go with

> Could someone explain to me how I should understand this?

The story is about a young man who tries to looking for diamonds.

This usage of "look" already means "trying to find".

Jamie wants to obtain his backupsupport and says the old man, "I'll bring you back more diamonds than you can count."

"Backing" means to supply financial support. "Backup" is used more for physical support.

After this, the novel says,contains this line: "The old man silently studied him for what seemed to Jamie to be an eternity."

I don't understand this parenthesisquoted part.

These are parenthesis: ()

I think "study" means like "stare".

bingo. Looking at https://dictionary.goo.ne.jp/word/en/study/#ej-82365, I think it's like "（注意深く）探る". Without looking at that, I would have said "じっと見る".

Does the "for" mean time interval like "for two hours"?

Yes. We can simplify the sentence a little bit like so:

> "The man studied him for an eternity."

But now the meaning is a bit altered and it implies the studying never ended. Still, you could substitute "eternity" for "two hours" and observe it is grammatically equivalent.

Otherwise, is it an objective like "a gift for you" or "in order to"?

Hmm... I want to say no, but etymologically these two uses are probably correlated.

Otherwise, does it indicate reason like "because of"??

no

In other words, could I say, ¶
"The old man silently studied him while Jamie feels. To Jamie, it felt like an eternity"??

ジェイミーにとって、それは永遠のように感じられました。
Does "永遠のように感じられる" makes sense in Japanese, though? In English, we'll say things like "it felt like an eternity" or "that took forever!", but we're sometimes advised to express this more like "なかなか終わらないと思った"

A difficult phrase tofor me 2

I'm reading a novel and came across a difficult phrase for me to read.

Could you help me how I figure it out?

The story is about a young man who triesis trying to look for diamonds.

Rumor has it that the old man backs diggers of diamondamond miners.

Jamie wants to obtain hisget a backup and says to the old man, "I'll bring you back more diamonds than you can count."

I don't really know what you mean by "obtain a backup"

I don't understand this parenthesis part.

I think "study" means like "to stare"."

It means looking at your face intently to understand your reaction.

Is this correct?

Doe the "for" meanindicate a time interval, like "for two hours"?

Yes :)

Otherwise,r is it objective, like "a gift for you" or "in order to"?

Otherwise,r does it indicate a reason, like "because of"??

It would be a big help if you could check and advise melet me know.