sangdaebangui dari busangi aju simhaeyo.

상대방 literally means the other side/person/party. Depending on context, it can mean:

• the other person in a conversation or interaction
• the other party in something formal, like a contract or dispute
• an opponent in a competition

In this sentence, it most naturally means the other person or the other party.

의 marks possession or an of-relationship. So 상대방의 means the other person’s.

Here:

• 상대방의 다리 부상 = the other person’s leg injury

English often uses apostrophe-s, but Korean uses 의 for this kind of relationship.

Yes, 부상 means injury, but Korean often puts the body part before it to specify what kind of injury it is.

So:

• 부상 = injury
• 다리 부상 = leg injury

This is very natural in Korean. It works a lot like noun combinations in English, such as:

• arm injury
• head injury
• knee injury

By itself, 다리 can mean either leg or bridge. But in this sentence, 다리 부상 clearly means leg injury, so 다리 must mean leg.

Context usually makes the meaning obvious.

Not exactly.

• 부상 usually means a physical injury, especially from an accident, sports, combat, or some harmful event.
• 상처 usually means a wound, cut, or injury mark, and it can also mean an emotional hurt.

So 부상 sounds more like injury, while 상처 can sound more like wound.

In this sentence, 부상 is the better word because it refers to a serious leg injury in a broader sense, not just a visible cut.

심해요 comes from the descriptive verb/adjective 심하다, which means to be severe, serious, or bad.

The breakdown is:

• dictionary form: 심하다
• polite present form: 심해요

So 아주 심해요 means is very severe/serious.

아주 means very. It is a straightforward, neutral intensifier.

So:

• 아주 심해요 = is very severe

Compared with some other choices:

• 정말 심해요 = really severe
• 너무 심해요 = very/too severe, depending on context

아주 is simple and natural here, especially in explanatory or factual speech.

The ending -해요 is the polite non-formal style, often called 해요체. It is very common in everyday speech.

So 심해요 is polite, but not stiff or highly formal.

Compare:

• 심해요 = polite everyday style
• 심합니다 = more formal
• 심해 = casual/plain-to-close-friends style

A natural breakdown is:

• 상대방의 = the other person’s
• 다리 부상이 = leg injury + subject marker
• 아주 심해요 = is very severe

So the structure is basically:

[Possessor] + [thing that is severe] + [description]

Korean often puts the thing being described before the predicate. The sentence is very literally something like:

The other person’s leg injury is very severe.

이/가 is the subject marker. Since 부상 ends in a consonant, it takes 이.

So:

• 부상이 = the injury as the subject of the sentence

The thing that is 심해요 is the 부상.

Yes, it could, but the nuance would change.

• 상대방의 다리 부상이 아주 심해요.
  This neutrally presents the leg injury as the subject.

• 상대방의 다리 부상은 아주 심해요.
  This makes the leg injury more of a topic, often with a contrastive or topical feel, like as for the other person’s leg injury, it’s very severe.

Both are possible, but 이/가 is very natural when simply stating the condition.

Sometimes Korean drops 의, especially in casual speech, but in this sentence 상대방의 다리 부상 sounds cleaner and more natural.

You may hear things like:

• 상대방 다리 부상

But that can sound more compressed, headline-like, or less standard in ordinary speech. For learners, using 의 here is a good choice.

In Korean, descriptive verbs like 심하다 already function as the predicate, so you do not need a separate word like English is.

English says:

• The injury is severe

Korean says:

• 부상이 심해요
• literally, something like the injury severe-is

So 심해요 already carries the idea of is severe.

Yes, it is natural, especially in contexts like:

• describing a medical condition
• talking about an accident
• reporting someone’s injuries
• discussing sports or emergencies

That said, 상대방 is a bit neutral or situational. In ordinary conversation, if you know the person, you might use a more specific noun instead, such as:

• 그 사람의 다리 부상이 아주 심해요. = That person’s leg injury is very severe.
• 환자의 다리 부상이 아주 심해요. = The patient’s leg injury is very severe.

It sounds fairly objective and factual.

• 부상 is a somewhat clinical or report-like word
• 아주 심해요 states severity clearly
• the -해요 ending keeps it polite and conversational

So the overall tone is polite and matter-of-fact, not especially dramatic or emotional.