haesbichi ganghaeseo sugeoneul beranda-e neoreo dueosseoyo.

이/가 marks 햇빛 as the subject of 강하다 (to be strong). The sentence is simply stating a condition:

• 햇빛이 강하다 = The sunlight is strong

Using 은/는 would make 햇빛 more of a topic, often with a contrast or a general-comment feeling:

• 햇빛은 강해서... = As for the sunlight, it was strong, so...

In this sentence, 햇빛이 강해서 sounds very natural and neutral.

강해서 comes from 강하다 (to be strong) plus -아서/어서, which connects two clauses and often means because, since, or so.

Formation:

• 강하다
• stem: 강하-
• -아서/어서 attached to 하다 verbs/adjectives often becomes 해서
• so: 강해서

So:

• 햇빛이 강해서 = because the sunlight is strong / since the sunlight is strong

It links the reason to the result.

Structure:

• 햇빛이 강해서 = because the sunlight is strong
• 수건을 베란다에 널어 두었어요 = I hung the towel(s) on the veranda and left them there

So the whole sentence follows a common Korean pattern:

• reason + -아서/어서 + result

This is one of the most basic and natural ways to say because/since/so in Korean.

These particles show the role of each noun:

• 수건을: 을/를 marks the direct object

  • 수건을 널다 = to hang out the towel(s)

• 베란다에: 에 marks the location where something is placed or happens

  • 베란다에 널다 = to hang it on/in the veranda area

So:

• 수건을 = the thing being hung
• 베란다에 = the place where it is hung

널다 means to hang out, to spread out, especially for drying things like laundry.

It is commonly used with things such as:

• 빨래를 널다 = to hang out the laundry
• 수건을 널다 = to hang out a towel / towels
• 이불을 널다 = to hang out bedding

A learner might compare it with 걸다 (to hang), but 널다 is especially natural for laundry or things spread out to dry. So in this sentence, 널다 is exactly the right verb.

This is a very important pattern.

-아/어 두다 means:

• do something and leave it that way
• do something in advance
• do something and keep the result/state

So:

• 널었어요 = I hung it/them out
• 널어 두었어요 = I hung it/them out and left it/them there / I put it/them out to dry

In this sentence, 널어 두었어요 suggests that the towels were hung out because of the strong sunlight, and they were left there intentionally, probably to dry.

Yes. Both are related.

The base verb is 두다 (to put, to leave). In this grammar pattern:

• 널어 두었어요 = full form
• 널어 뒀어요 = contracted form

Both mean essentially the same thing.
The contracted form 뒀어요 is very common in speech.

A useful note:

• 두었어요 = slightly fuller, less contracted
• 뒀어요 = very common spoken form

Learners should also know that 둬었어요 is not the standard spelling.

Because the speaker is talking about a completed action:

• I hung the towel(s) out

But with -어 두다, the past tense often still suggests a current result:

• the action was completed earlier
• the resulting state may still continue now

So 널어 두었어요 often implies something like:

• I put them out to dry, and they’re left there

Even though the verb is past tense, the effect may still be relevant in the present.

It can mean either a towel or towels.

Korean often does not mark singular vs. plural unless it is important. So:

• 수건을 널어 두었어요 could mean
  
  • I hung out a towel
  • I hung out the towels

You figure it out from context.

If the speaker wants to be specific, they can say things like:

• 수건 하나 = one towel
• 수건 두 장 = two towels
• 수건들 = towels (explicit plural, though often unnecessary)

No. 베란다 is a loanword, from veranda/verandah.

In Korean, 베란다 usually refers to a balcony-like space or enclosed balcony area in an apartment or home, and it is a very common place to dry laundry.

So 베란다에 널어 두었어요 sounds very natural in everyday Korean.

Yes. In English, the best translation depends on style.

-아서/어서 often expresses cause and result, so these can all work depending on context:

• because the sunlight was strong
• since the sunlight was strong
• the sunlight was strong, so...

That means the Korean sentence can naturally match different English wordings, even though the grammar is the same.