Learn Hardcore Russian: В дождливый день я не еду на велосипеде, а иду пешком до метро. - On a rainy day I don’t go by bicycle, but walk to the metro.

в дождливый день – accusative singular
– literally: into / on a rainy day → idiomatic: on a rainy day
в дождливом дне – prepositional singular
– this would sound very strange and is not used as a time expression.

Other similar examples:

в понедельник – on Monday
в этот день – on this day
в прошлую зиму – last winter

So в + accusative is the normal pattern for “on [a day] / in [a season / period]” as a time reference.

2. Could it also be в дождливые дни? What is the difference?

Yes, you can say:

В дождливые дни я не еду на велосипеде… – On rainy days I don’t go by bike…

The difference:

в дождливый день – singular: more like “on a rainy day” or “on this kind of day”. It can refer to a specific rainy day (e.g., today) or describe a typical behavior on such a day.
в дождливые дни – plural: clearly means “on rainy days (whenever it’s rainy, in general)”.

Both are grammatically correct; the choice depends on whether you want to sound more general (plural) or keep it closer to a specific day / type of day (singular).

3. Why is it я не еду на велосипеде and not я не езжу на велосипеде?

Both are possible, but they mean slightly different things:

я не еду на велосипеде (from ехать) – one‑direction, “go (by transport) now / this time”.
- Typically about a specific trip right now or today.
- In the sentence, it can mean: On this rainy day, I’m not going by bike (now), but walking to the metro.
я не езжу на велосипеде (from ездить) – multi‑direction, repeated / habitual movement.
- Describes general habits or repeated actions.
- Then the sentence would mean: On rainy days I don’t travel by bike (as a rule), but I walk to the metro.

So:

Talking about today’s decision (it’s rainy now): я не еду на велосипеде is natural.
Talking about your general habit whenever it rains: я не езжу на велосипеде is more appropriate.

4. What is the basic difference between ехать and идти in this sentence?

They contrast type of movement:

ехать – to go by some transport / vehicle (car, bus, train, bicycle, etc.)
идти – to go on foot (to walk in one direction)

So:

я не еду на велосипеде – I am not going by bike (using a vehicle).
а иду пешком – but I am going on foot.

Russian uses different verbs of motion depending on whether you use transport (ехать / ездить) or your feet (идти / ходить).

5. Why do we say на велосипеде and not something like велосипедом?

After verbs of moving by transport, Russian usually uses на + prepositional case to show the means of transport:

ехать на велосипеде – go by bike
ехать на автобусе – go by bus
ехать на поезде – go by train

The form велосипедом is the instrumental case and normally is not used to mean “by bike” in this context. It can appear with different verbs, for example:

управлять велосипедом – to control / steer a bicycle
гордиться велосипедом – to be proud of a bicycle

But for “go by bike” the natural phrase is ехать на велосипеде, not ехать велосипедом.

6. What exactly does пешком mean, and why do we need иду пешком?

Пешком is an adverb meaning “on foot”.

идти пешком – to go on foot, to walk (as a means of transport, not for fun).

You can say simply я иду до метро, and context will often make it clear that you are walking. But иду пешком:

explicitly contrasts with еду на велосипеде (by bike vs on foot),
removes any possible ambiguity and sounds very natural in this contrast:
не еду на велосипеде, а иду пешком – not going by bike, but going on foot.

So пешком works like an adverb clarifying how you are going.

7. Why is it иду пешком, not хожу пешком here?

Difference:

идти – one‑direction, one specific movement: “I am going (now / this time)”.
ходить – multi‑direction, habitual, or “back and forth”: “I (usually) go”.

In this sentence, иду пешком suggests:

one concrete trip to the metro (on this rainy day), or
the direction of the movement (from home to metro).

If you said:

Я в дождливый день не езжу на велосипеде, а хожу пешком до метро.

…that would sound more like a general habit: “On rainy days, I don’t go by bike, I (normally) walk to the metro.” Both are valid, but:

иду пешком → focuses on this particular walk / direction.
хожу пешком → emphasizes the habitual pattern.

8. Why is а used (…не еду на велосипеде, а иду пешком…) instead of но?

Both а and но can translate as “but”, but they are used differently.

а – contrastive “but”, opposes two actions or qualities; often like “but rather”.
- не еду на велосипеде, а иду пешком –
  not going by bike, but (instead) going on foot.
но – adversative “but”, often implies an obstacle or concession.
- Я хотел поехать на велосипеде, но идёт дождь.
  I wanted to go by bike, but it’s raining.

In our sentence, the speaker is contrasting two alternative ways of getting to the metro (bike vs walking), so а is the natural choice.

9. Why is it до метро and not к метро?

Both до and к can relate to movement toward something, but they mean different things:

до + genitive – up to / as far as some point (the end point of your movement).
- идти до метро – to walk to the metro (up to the station).
к + dative – towards / in the direction of something, often emphasizing direction, not necessarily reaching the exact end point.
- идти к метро – to walk towards the metro (direction).

In practice, when you mean you actually reach the metro, до метро is more natural:

иду пешком до метро – I walk all the way to the metro.

к метро could be used, but it would slightly shift the nuance to “in the direction of the metro”.

10. Why does метро stay the same in до метро? Shouldn’t the form change?

Метро is an indeclinable neuter noun (the form doesn’t change in different cases). So:

Nominative: метро – the metro
Genitive: метро – (after до)
Prepositional: в метро – in the metro

Even though до requires the genitive case, you don’t see a change in the ending because метро is indeclinable. The case is shown by the preposition, not by the noun ending in this particular word.

11. Why is the present tense (я не еду, я иду) used if the sentence can describe a habit?

In Russian, the present tense of imperfective verbs can express:

An action happening right now
- Сейчас я не еду на велосипеде, а иду пешком.
A regular, habitual action
- В дождливый день я не еду на велосипеде, а иду пешком до метро.
  → “On a rainy day I don’t (normally) go by bike but walk to the metro.”

English often uses the present simple for habits, which matches this Russian use quite well:

English: On rainy days I don’t go by bike, I walk.
Russian: В дождливый день я не еду на велосипеде, а иду пешком.

So the Russian present here can be understood as a general rule / habit.

12. Why is it иду, not пойду?

Идти and пойти are different aspects of the same verb of motion:

идти – imperfective: focuses on the process of going.
пойти – perfective: focuses on the start / completion of going; usually future or completed action.

Compare:

Я иду до метро. – I’m going / I walk to the metro (process, how I get there).
Я пойду до метро. – I will (at some point) go to the metro (decision, future action).

In this sentence, the contrast is about how the speaker gets there (by bike vs on foot), not about the moment of starting to go. So the process verb иду is more natural:

не еду на велосипеде, а иду пешком – not going by bike, but (instead) going on foot.

13. Could we say в метро instead of до метро? What would change?

Yes, you can say иду пешком в метро, but the meaning is slightly different:

идти до метро – to walk up to the metro station (the station is your end point).
идти в метро – to walk into the metro system / inside the metro (emphasis on entering the metro).

In everyday speech, if you are simply talking about getting from home to the metro station, до метро is more standard and precise. В метро is more about going inside the metro (e.g., into the building or underground system).

14. Why does the sentence start with В дождливый день? Could it be at the end?

Yes, it can be moved:

Я в дождливый день не еду на велосипеде, а иду пешком до метро.

Both orders are grammatically correct. Word order in Russian is relatively flexible and often used for emphasis:

В дождливый день я не еду на велосипеде…
– Emphasis on the condition / time: On a rainy day, (that’s when) I don’t go by bike…
Я не еду на велосипеде в дождливый день…
– Slightly more emphasis on “I” and “not going by bike”, with the time added later.

Starting with В дождливый день is a natural way to set the context first: “On a rainy day…” and then explain what you do in that situation.