gireul jalmos deureoseo da-eum sinhokkaji jikjinhaesseo.

In this sentence, 길을 들다 is a common expression meaning to take a road/path.

So 길 is treated as the object of 들다, which is why it takes 을:

• 길을 들다 = to take a road
• 길을 잘못 들다 = to take the wrong road

This is different from just saying you are on a road or at a place, where you would use particles like 에 or 에서.

So:

• 길을 잘못 들어서 = because I took the wrong road / after taking the wrong road

잘못 means wrongly / by mistake.

들어서 is from 들다, and here it means to enter/take a road or path. So:

• 잘못 들다 = to take the wrong one by mistake
• 잘못 들어서 = having taken the wrong one / because I took the wrong one

The -어서 ending connects this part to the next action. In natural English, it often sounds like:

• I took the wrong road, so...
• Because I went the wrong way...
• After taking the wrong road...

Here it is from 들다, not 들어가다.

That can be confusing because 들다 changes form:

• dictionary form: 들다
• connective form: 들어
• with -서: 들어서

In this sentence, 들다 means something like to enter/take a route.

So 길을 잘못 들어서 is not really went inside in the sense of 들어가다. It is more like took the wrong road/path.

-아서/어서 links two actions or clauses. Here it shows that the first action leads into the second.

• 길을 잘못 들어서
• 다음 신호까지 직진했어

So the meaning is roughly:

• I took the wrong road, so I went straight until the next light
• After taking the wrong road, I went straight until the next signal

It can express:

• sequence: one thing happened, then the next
• reason/cause: because of the first thing, the second happened

Here both ideas fit well.

다음 = next
신호 = signal, and in driving contexts it usually means traffic light
까지 = up to / until / as far as

So 다음 신호까지 means:

• until the next traffic light
• as far as the next signal

In real-life usage, 신호 can sometimes refer not just to the light itself, but to the signalized intersection area. So depending on context, it may feel like:

• until the next traffic light
• up to the next intersection with a light

Because 까지 marks the endpoint of movement.

• 다음 신호까지 직진했어 = I went straight until/as far as the next light

If you used 에서, it would mean at the next signal/light, which changes the meaning:

• 다음 신호에서 = at the next light

So:

• 까지 focuses on how far
• 에서 would focus on what happened there

In this sentence, the speaker is saying how far they continued going straight.

직진하다 means to go straight.

So:

• 직진했어 = went straight

It is the past tense informal form:

• dictionary form: 직진하다
• past: 직진했다
• casual spoken style: 직진했어

This is a very common verb in driving or direction-related situations.

했어 is the informal casual ending. It is used with:

• close friends
• younger people
• family
• diary-style narration
• casual conversation

The same sentence in more polite speech would be:

• 길을 잘못 들어서 다음 신호까지 직진했어요.

And in formal style:

• 길을 잘못 들어서 다음 신호까지 직진했습니다.

So the original sentence sounds conversational and informal.

Korean often drops the subject when it is already clear from context.

So although the sentence does not say I, we, or he/she, the listener usually understands it from the situation.

Depending on context, this could mean:

• I took the wrong road and went straight until the next light
• We took the wrong road and went straight until the next light

In many everyday Korean sentences, leaving out the subject sounds more natural than stating it explicitly.

Not always. The basic meaning of 신호 is signal.

Depending on context, it can mean:

• a general signal
• a traffic signal/light
• sometimes, by extension, the signalized intersection

In a sentence about driving directions like this one, native speakers will normally understand 신호 as traffic light.

So 다음 신호까지 is most naturally understood as until the next traffic light.

Yes. That is a very natural nuance here.

Because of -어서, the sentence can suggest that:

• the speaker took the wrong road
• and as a result, kept going straight until the next traffic light

So the mistake and the action are connected. It is not just two random actions in sequence; the second feels like it follows from the first.

That is why a natural English translation often includes so:

• I took the wrong road, so I went straight until the next light.

Yes, that is a good idea.

길을 잘못 들다 is a very useful everyday expression meaning:

• to take the wrong road
• to go the wrong way
• to get onto the wrong route

Learning it as a chunk will help because the grammar may not feel obvious at first to English speakers.

Useful related expressions:

• 길을 들다 = to take a road/path
• 길을 잘못 들다 = to take the wrong road
• 길을 잃다 = to get lost

These are similar, but not identical:

• 길을 잘못 들다 = you chose the wrong road
• 길을 잃다 = you are lost

The original sentence already means went straight until/as far as the next light, but if you want to make the sequencing more explicit, you could continue with another clause, for example:

• 길을 잘못 들어서 다음 신호까지 직진한 다음에 돌아왔어.
  • I took the wrong road, went straight until the next light, and then turned back.

Or:

• 길을 잘못 들어서 다음 신호까지 가서 유턴했어.
  • I took the wrong road, went as far as the next light, and made a U-turn.

So 다음 신호까지 직진했어 already gives the endpoint, but extra wording can make the next step clearer.