Questions & Answers about geu jip adeureun ajik eoryeoseo honja jihacheoreul tal jul molla.
Why does 그 집 mean a family or household here, not just a physical house?
In Korean, 집 can mean both:
- a house/home
- the household/family that lives there
So 그 집 아들 is a very natural way to mean that family's son or the son from that house.
This is common in Korean. Instead of using a possessive like their son, Korean often identifies someone through the household or group they belong to.
Why is it 아들은 and not 아들이?
은/는 is the topic marker, while 이/가 is the subject marker.
Here, 아들은 presents the son as the topic:
As for that family's son, ...
This can sound like the speaker is making a comment about him in particular. It may also carry a slight contrast, such as:
- The son, at least, is still too young...
- As for their son, he doesn't know how to...
If you used 아들이, the sentence would feel a bit more like simply identifying the subject, without that topical feel.
What does 아직 mean here?
아직 means still or yet, depending on the sentence.
In this sentence, it means still:
- 아직 어려서 = because he is still young
It suggests that the situation may change later. In other words, he is young for now, so he cannot do this yet.
Why is it 어려서?
어려서 comes from 어리다 (to be young) + -아서/어서.
The ending -아서/어서 often connects clauses and can mean:
- because
- so
- sometimes just a natural sequence
Here it gives the reason:
- 아직 어려서 = because he is still young
So the structure is:
- 어리다 → 어려서
This is an irregular-looking change only because of how 어리다 is conjugated:
- 어리다
- 어려요
- 어려서
Could 어려서 be replaced with 어리니까?
Yes, and the meaning would be very similar.
- 어려서 = because he is young / being young, so...
- 어리니까 = because he is young
The difference is mostly in tone and style:
- -아서/어서 often sounds smoother and more neutral
- -(으)니까 can sound a bit more explicit, like the speaker is clearly stating a reason
So 아직 어려서 feels very natural and conversational here.
What does 혼자 do in this sentence?
혼자 means alone or by oneself.
It tells you how he would ride the subway:
- 혼자 지하철을 타다 = to ride the subway alone
Its position is normal. In Korean, adverb-like words such as 혼자 often come before the object and verb.
So:
- 혼자 지하철을 탈 줄 몰라
means he does not know how to ride the subway by himself
Why is it 지하철을 타다? Why use 을 with a vehicle?
In Korean, 타다 is the verb used for riding or taking transportation, and the vehicle is marked as its object with 을/를.
So Korean says:
- 버스를 타다 = ride/take the bus
- 택시를 타다 = ride/take a taxi
- 지하철을 타다 = ride/take the subway
This is different from English, where we often use prepositions like on or by instead of making the vehicle a direct object.
Why does 타다 become 탈?
This is because the pattern -(으)ㄹ 줄 알다 / 모르다 requires the verb to appear in the -(으)ㄹ form.
So:
- 타다 → 탈
- 먹다 → 먹을
- 가다 → 갈
In this sentence:
- 지하철을 탈 줄 몰라
the 탈 is not a separate word by itself; it is part of the grammar pattern -(으)ㄹ 줄 모르다.
What does -(으)ㄹ 줄 모르다 mean?
This pattern means to not know how to do something.
Structure:
- verb stem + -(으)ㄹ 줄 알다 = to know how to do
- verb stem + -(으)ㄹ 줄 모르다 = to not know how to do
So:
- 탈 줄 알다 = know how to ride
- 탈 줄 모르다 = not know how to ride / not know how to do it
In real usage, -(으)ㄹ 줄 모르다 often overlaps with English can't, especially when the inability comes from lack of knowledge, experience, or skill.
So here it implies something like:
- he doesn't know how to ride the subway alone
- he can't ride the subway alone by himself
Why use 탈 줄 몰라 instead of something like 못 타?
Good question. These are similar, but not exactly the same.
- 못 타 = cannot ride / is unable to ride
- 탈 줄 몰라 = does not know how to ride
못 타 focuses on the inability itself.
탈 줄 몰라 focuses more on not knowing how.
In this sentence, 탈 줄 몰라 fits well because the idea is that the child is too young to know how to manage riding the subway alone.
So the nuance is not just physical inability, but lack of know-how or readiness.
Why does the sentence end with 몰라 instead of 몰라요?
몰라 is the plain informal style.
It is commonly used:
- in casual speech
- in narration
- in examples and textbook sentences
- when speaking to close friends or younger people
A more polite version would be:
- 그 집 아들은 아직 어려서 혼자 지하철을 탈 줄 몰라요.
And a more formal version would be:
- 그 집 아들은 아직 어려서 혼자 지하철을 탈 줄 모릅니다.
So the grammar is the same; only the speech level changes.
Is the subject he omitted in the second part of the sentence?
Yes. Korean often omits subjects when they are already clear from context.
After 그 집 아들은, we already know who the sentence is about, so Korean does not need to repeat he before 혼자 지하철을 탈 줄 몰라.
English usually repeats the subject:
- That family's son is still young, so he doesn't know how to ride the subway alone.
Korean often leaves it out because it is understood.
Is 그 집 아들 the same as 그 집의 아들?
They are very close in meaning, but 그 집 아들 is much more natural in everyday Korean.
- 그 집 아들 = natural, common
- 그 집의 아들 = grammatical, but more formal or stiff
Korean often leaves out 의 in possessive relationships when the meaning is obvious.
So in normal conversation, 그 집 아들 is exactly what you would expect to hear.
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