i keompyuteoneun oraedwaessjiman ajik jal jakdonghaeyo.

는 is the topic particle. It marks 이 컴퓨터 as the thing the sentence is about: as for this computer...

So the sentence is structured like:

• 이 컴퓨터는 = as for this computer
• 오래됐지만 아직 잘 작동해요 = although it’s old, it still works well

A native English speaker often expects a clear subject every time, but Korean often starts by setting a topic instead. That topic can then carry through the rest of the sentence.

Yes, but the nuance changes.

• 이 컴퓨터는 오래됐지만 아직 잘 작동해요.
  = As for this computer, it’s old, but it still works well.

• 이 컴퓨터가 오래됐지만 아직 잘 작동해요.
  is less natural in a neutral situation, and 가 would put more focus on this computer itself as the subject.

In many everyday statements like this, 는 sounds more natural because you are introducing or commenting on a topic.

A simple way to think about it:

• 는 = topic / contrast / general comment
• 가 = subject / focus / identification

The base form is 오래되다.

It breaks down like this:

• 오래되다 = to become old; to be old; to have been around a long time
• 오래됐다 = became old / has gotten old / is old now
• 오래됐지만 = although it has become old / although it is old

So -지만 is attached to a conjugated form of 오래되다.

This is a very common question.

오래되다 literally has the sense of to become old / to have gotten old over time. Because of that, Korean often uses the past form to describe the current state that resulted from that change.

So 오래됐어요 often means:

• it has gotten old
• it’s old now

This is similar to how English sometimes says It has aged or It’s gotten old, even when we are talking about its current condition.

So in this sentence, 오래됐지만 does not feel like a simple completed past event. It describes the computer’s present state as something that happened over time.

-지만 means but, although, or even though.

Here:

• 오래됐지만 = although it’s old / but it’s old

So the sentence has a contrast:

• it’s old
• but it still works well

In Korean, -지만 is attached directly to the verb or adjective stem after conjugation as needed.

A few similar examples:

• 비싸지만 좋아요. = It’s expensive, but it’s good.
• 작지만 편해요. = It’s small, but it’s comfortable.

Here, 아직 means still.

• 아직 잘 작동해요 = it still works well

A useful rule:

• In positive sentences, 아직 often means still
• In negative sentences, 아직 often means yet

For example:

• 아직 있어요. = It’s still there.
• 아직 안 왔어요. = He/She hasn’t come yet.

So in this sentence, 아직 emphasizes that even though the computer is old, it continues to function well.

Yes, 잘 literally means well, but in this kind of sentence it often means:

• properly
• smoothly
• without problems

So 잘 작동해요 means:

• works well
• functions properly

This is very common in Korean. 잘 is often used with verbs to mean that something is done successfully or in a satisfactory way.

Examples:

• 잘 먹어요. = eats well
• 잘 알아요. = knows well
• 잘 돼요. = goes well / works out

작동하다 specifically means to operate or to function, especially for machines, devices, and systems.

So for a computer, 작동하다 is very natural because you are talking about whether it functions properly.

English uses work for many things, but Korean often chooses different verbs depending on what kind of working you mean:

• 작동하다 = to operate/function mechanically
• 일하다 = to work at a job
• 통하다 or 먹히다 can appear in other contexts with different meanings

So for a computer, 작동하다 is a good fit.

This is a standard 하다 conjugation.

• dictionary form: 작동하다
• polite present: 작동해요

That happens because:

• 하다 → 해요

So:

• 작동하다 → 작동해요
• 공부하다 → 공부해요
• 운동하다 → 운동해요

This pattern is extremely common because many Korean verbs are noun + 하다 combinations.

It is a contraction.

Step by step:

• 오래되다
• 오래되었지만 = full form
• 오래됐지만 = contracted, natural spoken/written form

In everyday Korean, 되었 very often contracts to 됐:

• 되었어요 → 됐어요
• 안 되었어요 → 안 됐어요
• 오래되었어요 → 오래됐어요

So 오래됐지만 is just the normal shortened form.

Because Korean often omits subjects and objects when they are already understood from context.

Once the sentence starts with 이 컴퓨터는, Korean does not need to repeat it. The rest is understood as describing that computer.

So Korean naturally says:

• 이 컴퓨터는 오래됐지만 아직 잘 작동해요.

English usually prefers:

• This computer is old, but it still works well.

Korean is comfortable leaving out words that are obvious from context.

Yes. It uses the 해요-style, which is polite and very common in everyday conversation.

The final verb is:

• 작동해요

This makes the whole sentence sound polite but not overly formal.

Roughly speaking:

• 작동해요 = polite everyday
• 작동합니다 = more formal
• 작동해 = casual

So this sentence would be appropriate in normal conversation, customer service, or speaking politely to someone you do not know very closely.

It is a little different.

오래되다 is often used for things that have existed for a long time or have gotten old with age:

• buildings
• furniture
• computers
• stories
• traditions

It does not mean old in every possible sense. For example:

• For an old person, you would not use 오래되다
• For something worn out, 낡다 may be more appropriate

So 오래됐다 suggests the computer has been around a long time. It does not necessarily mean it is broken or shabby. That is why the contrast with still works well makes sense.

A helpful breakdown is:

• 이 = this
• 컴퓨터는 = as for the computer
• 오래됐지만 = although it is old
• 아직 = still
• 잘 = well
• 작동해요 = operates / works

So the overall order is roughly:

This computer + topic + although old + still + well + works

Korean usually puts the main verb at the end, and adverbs like 아직 and 잘 come before the verb they describe.

That is why 잘 작동해요 sounds natural, not 작동 잘 해요 in this sentence.