biga omyeon geotneun daesine jihacheoreul tayo.

비가 오면 literally means if rain comes or more naturally if it rains / when it rains.

• 비 = rain
• 오다 = to come
• 비가 오다 is the standard Korean expression for to rain

Korean treats rain as the thing that comes, so it uses the subject marker 가, not the object marker 를.

So:

• 비가 와요 = It rains / It is raining
• 비가 오면 = If it rains / When it rains

English and Korean just package this idea differently.

-면 is a conditional ending meaning if or sometimes when.

In this sentence:

• 비가 오면 = if it rains / when it rains

Whether it sounds more like if or when depends on context. Here, it could mean either:

• If it rains, I take the subway instead of walking
• When it rains, I take the subway instead of walking

It is commonly used for general conditions, habits, or future situations.

Examples:

• 시간이 있으면 가요. = If I have time, I go / I’ll go.
• 배고프면 먹어요. = If I’m hungry, I eat.

In 걷는 대신에, 걷는 is the modifier form of the verb 걷다 (to walk). It is being used to describe the omitted idea 것 or to connect naturally to 대신에.

So:

• 걷다 = to walk
• 걷는 대신에 = instead of walking

This structure is very common:

• 먹는 대신에 = instead of eating
• 가는 대신에 = instead of going
• 공부하는 대신에 = instead of studying

You may also see 걷기 instead of walking in other contexts, but verb + 는 대신에 is a very standard and natural pattern.

This is the present-tense verb modifier form for action verbs.

For most action verbs, you attach -는 to the verb stem:

• 가다 → 가는
• 먹다 → 먹는
• 걷다 → 걷는

So 걷는 means something like walking or that one walks, depending on context.

In this sentence, it works as:

• 걷는 대신에 = instead of walking

This is not the same as a full conjugated sentence like 걸어요 (I walk / walk). Here, the verb is modifying the phrase before 대신에.

대신에 means instead of or in place of.

In this sentence:

• 걷는 대신에 지하철을 타요 = I take the subway instead of walking.

It sets up a contrast between two choices:

1. walking
2. taking the subway

A few more examples:

• 커피 대신에 차를 마셔요. = I drink tea instead of coffee.
• 집에 있는 대신에 나갔어요. = I went out instead of staying home.

So here, 대신에 shows substitution: one action is done in place of another.

Great question. 지하철을 is the object of 타요.

• 지하철 = subway
• 타다 = to ride / take
• 지하철을 타요 = take the subway / ride the subway

So 을 marks 지하철 as the object.

But 걷는 대신에 is not functioning as a regular object here. It is part of the fixed expression verb + 는 대신에, meaning instead of doing.

So the structure is:

• 비가 오면 = if it rains
• 걷는 대신에 = instead of walking
• 지하철을 타요 = take the subway

Korean uses 타다 for getting on and riding transportation such as:

• 버스를 타다 = take the bus
• 지하철을 타다 = take the subway
• 택시를 타다 = take a taxi
• 기차를 타다 = take a train

Literally, 타다 can mean ride, but in natural English translation it is often take for public transportation.

So:

• 지하철을 타요 could be translated as
  • I ride the subway
  • I take the subway

Both are fine, but take the subway usually sounds more natural in English.

It can most naturally describe a habit or general rule:

• When it rains, I take the subway instead of walking.

Because the sentence is in present polite style (타요) and uses -면, it often sounds like something the speaker usually does.

However, depending on context, it could also refer to a future situation:

• If it rains, I’ll take the subway instead of walking.

Korean often relies on context rather than separate future verb forms.

Korean often omits the subject when it is obvious from context.

So even though the sentence does not say 저는, it can still mean:

• I take the subway instead of walking if it rains
• When it rains, I take the subway instead of walking

If you want to make the subject explicit, you could say:

• 저는 비가 오면 걷는 대신에 지하철을 타요.

That means the same thing, just with I stated clearly.

Yes. Korean -면 often covers both ideas, and English chooses if or when based on context.

Here are the two possible interpretations:

• If it rains, I take the subway instead of walking.
• When it rains, I take the subway instead of walking.

If the speaker is talking about a usual pattern, English often prefers when. If the speaker is talking about a possible future event, English often prefers if.

Korean leaves that more open.

The sentence follows normal Korean word order: conditions and background information usually come before the main action.

Breakdown:

• 비가 오면 = if it rains
• 걷는 대신에 = instead of walking
• 지하철을 = the subway
• 타요 = take

So the overall pattern is:

[condition] + [instead of X] + [object] + [main verb]

A very literal order would be:

If rain comes, instead of walking, subway take.

That sounds strange in English, but it is completely natural in Korean.

Yes, that is possible if you want to make the contrast more explicit.

• 걷는 대신에 = instead of walking
• 걸어서 가는 대신에 = instead of going on foot / instead of walking there

Your version gives a slightly fuller idea of the action being replaced.

Compare:

• 비가 오면 걷는 대신에 지하철을 타요. = If it rains, I take the subway instead of walking.
• 비가 오면 걸어서 가는 대신에 지하철을 타요. = If it rains, I take the subway instead of going on foot.

The original sentence is already natural and clear.

Yes, they are related but not identical.

대신에 means instead of and strongly emphasizes replacement:

• 걷는 대신에 지하철을 타요. = I take the subway instead of walking.

말고 often means not X but Y or other than X:

• 지하철 말고 버스를 타요. = I take the bus, not the subway.
• 커피 말고 차 주세요. = Tea, not coffee, please.

So in this sentence, 대신에 is the better choice because the speaker is replacing one action with another.

타요 is in the standard polite style, which is appropriate in most everyday situations.

Levels:

• 타요 = polite, neutral, common
• 탑니다 = more formal
• 타 = casual/informal

So the sentence could vary like this:

• 비가 오면 걷는 대신에 지하철을 타요. = standard polite
• 비가 오면 걷는 대신에 지하철을 탑니다. = formal
• 비 오면 걷는 대신에 지하철 타. = casual

The original sentence is a good everyday style for learners to know.