undongbogeun orae neoreo dumyeon achimeneun geoui mallayo.

은 marks 운동복 as the topic: as for workout clothes...

The sentence is not just focusing on what you hang; it is making a general statement about workout clothes. A natural way to read it is:

• As for workout clothes, if you leave them hanging for a long time, by morning they’re almost dry.

If you used 운동복을, that would mark workout clothes as the direct object of 널다 more directly, but this sentence is structured more like a general observation, so 은 sounds very natural.

Also, once 운동복 is introduced as the topic, Korean often leaves the repeated object unstated later because it is already understood.

Yes. 운동복 literally means exercise clothes / sportswear / workout clothes.

Depending on context, it could refer to:

• gym clothes
• athletic wear
• a tracksuit
• clothes worn for exercise

In this sentence, workout clothes or sportswear is a very natural translation.

널다 means to hang something out to dry or to spread something out.

In laundry-related contexts, 널다 is the normal verb for hanging clothes up to dry.

Compare:

• 걸다 = to hang something on a hook, wall, hanger, etc.
• 널다 = to spread/hang something out, especially laundry, so it can dry

So here 운동복을 널다 means:

• to hang the workout clothes out to dry

That is why 널다 is the best choice in this sentence.

널어 두면 is made from:

• 널다 = to hang out to dry
• -어 두다 = to do something and leave it in that state
• -면 = if / when

So 널어 두면 means:

• if you hang them up and leave them that way
• if you leave them hanging

The grammar -아/어 두다 often gives the idea of:

• doing something in advance
• leaving something as it is
• keeping something in a certain state for later benefit/result

So this is not just hang them once. It is more like:

• hang them up and let them stay there

오래 means for a long time.

It is the adverb form related to 오랜 / 오래된 ideas of long duration. In this sentence, it modifies 널어 두면:

• 오래 널어 두면 = if you leave them hanging for a long time

So it is describing the duration of the clothes being left out.

아침에 simply means in the morning.

아침에는 adds 는, which gives a slight contrastive or topical nuance. It can feel like:

• by the morning
• when morning comes
• at least in the morning
• as for the morning time, ...

In this sentence, 아침에는 거의 말라요 sounds like:

• by morning, they’re almost dry
• when it’s morning, they’re almost dry

The 는 helps highlight that time point as the result stage of the situation.

거의 means almost / nearly.

So:

• 거의 말라요 = they’re almost dry

This tells you the clothes are not necessarily 100% dry, but very close.

It comes from 마르다, which means to become dry.

So:

• 마르다 = to dry, to become dry
• 말리다 = to dry something, to cause something to dry

That means:

• 옷이 말라요 = the clothes dry / become dry
• 옷을 말려요 = someone dries the clothes

In this sentence, the clothes themselves are becoming dry, so 마르다 is the correct verb.

Also, 마르다 conjugates irregularly:

• 마르다 → 말라요

This is a 르 irregular pattern.

Sure. A simple breakdown is:

• 운동복은 = as for workout clothes
• 오래 널어 두면 = if you hang them out and leave them for a long time
• 아침에는 = by morning / in the morning
• 거의 말라요 = they are almost dry

So the full structure is:

• Topic + condition + time/result frame + result

Very naturally, it means something like:

• As for workout clothes, if you leave them hanging out for a long time, they’re almost dry by morning.

That is very normal in Korean. The subject is often omitted when it is obvious or not important.

Here, the understood subject is something general like:

• you
• one
• people
• if someone does this

So 오래 널어 두면 is basically:

• if you leave them hanging
• if they are left hanging

Korean often leaves such subjects unstated, especially in general statements.

It sounds like a general statement or practical observation, not just one specific occasion.

Because of:

• the topic marker 은
• the conditional -면
• the plain present polite ending 말라요

the sentence feels like:

• Workout clothes, if you leave them hanging for a long time, are almost dry by morning.

In Korean, the present tense often covers general truths and regular results, so 말라요 here does not only mean what is happening right now. It can also express a habitual or predictable result.