Learn Hardcore Japanese: tosyokan no zisyuusitu ha sizukade, heddohon wo tukenakute mo benkyou ni syuutyuu dekiru. - The library’s self-study room is quiet, so I can concentrate on studying even without putting on headphones.

図書館の自習室 literally: “the library’s self-study room” / “the self-study room of the library”
So 図書館の is working like “library-” (a modifier) and 自習室 is the main noun.

Why is は attached to 自習室 and not to 図書館?

自習室は makes “the self-study room” the topic of the sentence.

図書館の自習室は〜 = “As for the library’s self-study room, …”

The speaker wants to talk specifically about the self-study room, not the library in general.
Putting は after 自習室 tells the listener: “Now I’m going to say something about the self-study room (of the library).”

What does 静かで mean, and why is it 静かで instead of 静かです or 静かだ?

静かで is the て-form of the な-adjective 静か (quiet).

静かだ = it is quiet (plain form)
静かです = it is quiet (polite form)
静かで = quiet and… / being quiet, … (connecting to the next part)

In this sentence:

静かで、ヘッドホンをつけなくても…
= “(It is) quiet, and (so) even without wearing headphones…”

The て-form connects this description to the next clause. It can suggest a simple “and” or a soft reason/cause (“because it’s quiet, …”) depending on context.

What does ヘッドホンをつける mean exactly? Does つける always mean “to wear”?

Here, ヘッドホンをつける means “to put on / to wear headphones.”

つける is used for things you attach to your body, often above the waist, like:

イヤホンをつける – put on earphones
ネクタイをつける – put on a tie
アクセサリーをつける – wear accessories

Japanese uses different verbs for different “wearing” actions (e.g., 着る, かぶる, はく, はめる, する, つける), and つける is one of them, especially for things you “attach” like headphones.

How is つけなくても formed, and what does it literally mean?

つけなくても comes from the verb つける (to put on).

Dictionary form: つける
Negative: つけない (not put on)
Negative て-form: つけなくて
Add も: つけなくても

The pattern 〜なくても means “even if (someone) doesn’t ~” or “without ~ing.”

So ヘッドホンをつけなくても literally:

“Even if (I/you) don’t put on headphones”
In natural English: “even without wearing headphones”

What is the function of も in つけなくても?

The も in 〜なくても adds the nuance of “even if”.

つけない – do not put on
つけなくて – not putting on and… / and not putting on…
つけなくても – even if (someone) does not put on / even without putting on

So in context, ヘッドホンをつけなくても means:

“Even if you don’t wear headphones / even without headphones, …”

It slightly emphasizes the contrast: You might expect that you need headphones, but actually, even if you don’t use them, it’s still fine.

What does 勉強に集中できる mean grammatically? How is it structured?

Breakdown:

勉強 – study, studying
勉強に – “on/for study” (に marks the target/focus of the concentration)
集中する – to concentrate
集中できる – can concentrate (potential form of 集中する)

So 勉強に集中できる literally means:

“(I/you) can concentrate on study.”

Grammatically:

集中する → potential form 集中できる (“be able to concentrate”)
〜に marks what you are concentrating on (勉強).

Why is it 勉強に集中できる and not 勉強を集中できる?

With 集中する, the thing you focus on is usually marked by に, not を.

〜に集中する = to concentrate on ~
- 勉強に集中する – concentrate on studying
- 仕事に集中する – concentrate on work
- 音楽に集中する – focus on the music

Using を would be unnatural here. For this verb, に is the standard particle for the focus/target of concentration.

Why is there no explicit subject like “I” or “you” in this sentence?

Japanese often omits the subject when it’s clear from context or when making general statements.

図書館の自習室は静かで、ヘッドホンをつけなくても勉強に集中できる。

This can be understood as:

“In the library’s self-study room, you can concentrate on your studies even without wearing headphones.”
or more generally: “One can concentrate on studying…”

The subject is implicit, and the listener fills in “I/you/people” based on context.

Could you rewrite the sentence with a more explicit “because” meaning, instead of just 静かで?

Yes. You can use forms that explicitly show a reason, such as から or ので:

図書館の自習室は静かだから、ヘッドホンをつけなくても勉強に集中できる。
図書館の自習室は静かなので、ヘッドホンをつけなくても勉強に集中できる。

Both mean roughly:

“Because the library’s self-study room is quiet, you can concentrate on studying even without headphones.”

The original 静かで is a bit softer/looser; it can be read as simply “and” or implying “and (therefore).”

Is 勉強に集中できる polite or plain? How would I say this politely?

集中できる is in the plain (dictionary) form.

To make it polite, use ます-form of できる:

勉強に集中できます。

So a fully polite version of the sentence would be:

図書館の自習室は静かで、ヘッドホンをつけなくても勉強に集中できます。
→ “The library’s self-study room is quiet, so you can concentrate on your studies even without wearing headphones.”