По дороге в метро я повторяю новые слова.

On the way to the metro, I review new words.

Breakdown of По дороге в метро я повторяю новые слова.

• я: I
• в: to
• новый: new
• слово: the word
• метро: the metro
• повторять: to review
• по дороге: on the way

Questions & Answers about По дороге в метро я повторяю новые слова.

Why does по require дороге (and what case is that)?

In по дороге (meaning on the way / along the road), по takes the dative case.

• дорога (dictionary form, nominative) → дороге (dative singular)
  This whole phrase works like an adverbial expression: по дороге = while on the way.

Is по дороге в метро literally “along the road into the metro”? Why в and not к?

по дороге в метро is an idiomatic way to say on the way to the metro.

• в + accusative often marks a destination (going to a place as an endpoint).
• к + dative means towards / up to something (often “to” a person or “to/near” a place).
  So both can be possible depending on nuance:
• по дороге в метро = on the way to the metro (as a destination)
• по дороге к метро = on the way towards the metro / up to the metro entrance

What case is метро here?

It’s accusative after в because it expresses destination (в + accusative).
But метро is indeclinable, so it looks the same in all cases: метро.

Why is the word order По дороге в метро first? Could it go elsewhere?

Yes, Russian word order is flexible. Putting По дороге в метро first sets the scene (time/situation) and sounds natural. Common alternatives:

• По дороге в метро я повторяю новые слова. (neutral, sets context first)
• Я по дороге в метро повторяю новые слова. (focus a bit more on я)
• Я повторяю новые слова по дороге в метро. (focus more on the action first)

Do I have to say я? Can it be omitted?

You can omit я if it’s clear who the subject is:

• По дороге в метро повторяю новые слова.
  Russian verb endings show the subject, so повторяю already implies I. Keeping я can add emphasis or contrast.

Why is повторяю imperfective? What would повторю mean?

повторять (imperfective) fits a habitual / repeated / ongoing meaning: you do it regularly on the way.
повторю (perfective, from повторить) would mean a single completed repetition, often with a “result” feel:

• По дороге в метро я повторю новые слова. = I’ll review the new words (and finish that review) on the way.

Is this present tense describing something happening right now or a routine?

It can be either, but this sentence very often implies a routine/habit: what you typically do on the way. Russian present tense with imperfective commonly expresses habitual actions without extra words like usually.

Why is новые слова in this form? What case is it?

It’s the direct object of повторяю, so it takes the accusative.
Because слова is inanimate plural, accusative plural = nominative plural in form:

• nominative plural: слова
• accusative plural (inanimate): слова
  And the adjective agrees:
• новые (plural, matches слова)

What if the object were animate—would it look different in accusative plural?

Yes. For animate plural nouns, accusative plural usually matches genitive plural.
Example pattern:

• inanimate: вижу столы (same as nominative plural)
• animate: вижу студентов (matches genitive plural студентов)
  In your sentence, слова is inanimate, so it stays слова.

Is по дороге the only way to say “on the way”? Any common alternatives?

A very common alternative is по пути:

• По пути в метро я повторяю новые слова.
  по дороге feels a bit more “literally on the road/route,” while по пути is often more general (“along the way”), but in many contexts they’re interchangeable.

How is this sentence pronounced (stress + any sound changes)?

Typical stress:

• по дорогЕ
• повторЯю
• нОвые
• словА
  Sound change: в метро is often pronounced with devoicing/assimilation, close to ф метрó in fast speech.

Could I say в пути instead of по пути?

You can, but it’s different in style and structure:

• по пути = a common conversational adverbial phrase (along the way)
• в пути = more like while en route / in transit, often used with verbs like быть:
  
  • Я в пути. = I’m on my way / I’m en route.
    So for your sentence, по пути в метро is the more natural match.