Learn Hardcore Japanese: kanozyo ha atarasii megane wo kau tame ni eki mae no meganeya ni ikimasita. - She went to the eyeglasses shop in front of the station to buy new glasses.

So 買うために is a purpose clause (to buy), and 行きました is the main action (went). Together:
新しい眼鏡を買うために行きました = (She) went in order to buy new glasses.

Why is を attached to 眼鏡 when the main verb is 行きました, not 買う?

The を here belongs to the verb 買う, not directly to 行きました.

Small clause: 新しい眼鏡を買う = “to buy new glasses”
→ in that clause, 新しい眼鏡 is the direct object, so it takes を.
This whole clause is then turned into a purpose phrase with ために:
- 新しい眼鏡を買うために = “in order to buy new glasses”.

So the structure is:

[新しい眼鏡を買う] ために行きました
The object marker を is doing its normal job inside the 買う clause.

Why are there two に particles in the sentence? Are they doing the same thing?

They look the same, but they have different roles:

買うために
- Here, に is part of the fixed pattern V‑dictionary form + ために = “in order to V”.
- It marks purpose.
メガネ屋に行きました
- Here, に marks the destination of 行きました (went).
- It means “to (the glasses shop)”.

So:

…買うために = in order to buy …
メガネ屋に行きました = went to the glasses shop.

They are the same particle に, but with different grammatical functions: purpose vs destination.

What exactly is 駅前のメガネ屋? How does 駅前 work with の?

Breakdown:

駅 = station
前 = front
駅前 (as a compound noun) = “the area in front of the station”, not just the literal few meters in front; it often means the station-front neighborhood.

Then:

駅前のメガネ屋
- メガネ屋 = glasses shop
- 駅前のメガネ屋 = “the glasses shop in front of the station” / “the station-front glasses shop”.

Here の links two nouns and can mean things like:

“located in/at”
“of / belonging to”
“in the area of”

So 駅前のメガネ屋 is “the glasses shop that is in the station-front area.”

Why is 眼鏡 written in kanji but メガネ屋 uses katakana メガネ instead of the kanji?

Both 眼鏡 and メガネ mean “glasses”.

眼鏡 (kanji): more traditional/standard dictionary form.
メガネ (katakana): very common in everyday writing; can feel a bit lighter, more modern, or brand‑name/store‑sign‑like.

In real Japanese, it’s common to mix:

眼鏡 in the explanatory part (e.g., 新しい眼鏡を買う),
メガネ屋 for the store name / type of store, which often appears in katakana on signs.

You could also write 眼鏡屋; it’s still correct. The choice is mostly about style and feel, not a difference in basic meaning.

What does 屋 mean in メガネ屋?

屋 (や) often means “shop / store for X” or “person who does X”, depending on context.

パン屋 = bakery (bread shop)
本屋 = bookstore
花屋 = florist
メガネ屋 = glasses shop / optician’s (informal term)

So メガネ屋 literally is “glasses shop.”

What is the difference between 彼女は and 彼女が here?

In this sentence, 彼女は is natural because:

は marks the topic: “As for her, …”
The sentence is just telling you what she did; she’s the topic of the narrative.

If you used 彼女が, it would:

Mark 彼女 as the grammatical subject and often emphasize or contrast her:
- e.g. implying “She (as opposed to someone else) went to the shop.”

Both can be grammatically possible, but:

彼女は … 行きました sounds like neutral narration.
彼女が … 行きました would be used when you specifically want to highlight she in contrast to others.

Can I change the order of the parts, like: 彼女は駅前のメガネ屋に新しい眼鏡を買うために行きました?

Yes, you can reorder many parts before the verb in Japanese. Both are acceptable:

彼女は新しい眼鏡を買うために駅前のメガネ屋に行きました。
彼女は駅前のメガネ屋に新しい眼鏡を買うために行きました。

The meaning is essentially the same: “She went to the glasses shop in front of the station in order to buy new glasses.”

Key rule:

The main verb (行きました) must stay at the end.
Modifiers like purpose phrases and destination phrases can be swapped around before the verb, within reason.

How would this sentence look in casual (informal) speech?

Most commonly, you would just change the verb to the plain past:

彼女は新しい眼鏡を買うために駅前のメガネ屋に行った。

Other possible casual variations:

Drop 彼女は if it’s already clear who you’re talking about:
新しい眼鏡を買うために駅前のメガネ屋に行った。
Or make it slightly explanatory:
新しい眼鏡を買うために駅前のメガネ屋に行ったんだ。

The politeness difference mainly shows up in 行きました → 行った.

Why is 新しい placed before 眼鏡 instead of after it, like in English “glasses new”?

In Japanese, i‑adjectives like 新しい always come before the noun they directly modify:

新しい眼鏡 = “new glasses”
大きい家 = “big house”
面白い本 = “interesting book”

You cannot say 眼鏡新しい as a single noun phrase. If you want “the glasses are new,” you need a full sentence structure:

眼鏡は新しいです。 = “The glasses are new.”

Does 彼女 mean “she” or “girlfriend” here? How can I tell?

彼女 can mean both:

“she / her” (3rd‑person pronoun)
“girlfriend”

In this one sentence alone, it’s ambiguous. You need context:

If the story is narrating about a female person in general, 彼女 = she.
If someone is talking about their romantic partner, 彼女 usually = girlfriend:
- e.g. 彼女とデートに行きました。 = “I went on a date with my girlfriend.”

Example sentences in textbooks often intend “she”, unless it’s clearly about relationships.

Could I say 新しい眼鏡を買いに駅前のメガネ屋に行きました instead? What’s the difference between 買うために and 買いに?

Yes, that’s very natural:

新しい眼鏡を買いに駅前のメガネ屋に行きました。

Comparison:

買うために行きました
- Pattern: V‑dictionary form + ために + 行く
- Meaning: “went in order to buy …”
- Slightly more formal / explanatory; can be used in writing, or when emphasizing reason/purpose.
買いに行きました
- Pattern: V‑ます‑stem + に + 行く
- Meaning: “went to buy …”
- Very common and colloquial, especially in spoken Japanese.

In everyday speech, 新しい眼鏡を買いに駅前のメガネ屋に行きました (or 行った) might be the most natural version, but 買うために is also perfectly correct and just a bit more neutral/formal in tone.