johahaneun eumageul deureumyeon gibuni johajyeoyo.

Because 좋아하는 is a verb form that modifies a noun.

• 좋아하다 = to like
• 좋아하는 음악 = music that (someone) likes / favorite music

In Korean, verbs can directly describe nouns this way. So instead of saying something like liked music or music that I like with a separate relative clause as in English, Korean often puts the modifying verb form right before the noun:

• 좋아하는 음식 = food I like
• 읽는 책 = the book I’m reading

Here, 좋아하는 음악 means music one likes.

을 is the object marker.

In this sentence, 음악 is the thing being listened to, and the verb 듣다 means to listen to / hear. So:

• 음악을 듣다 = to listen to music

Korean often marks the direct object with 을/를:

• consonant ending + 을
• vowel ending + 를

Since 음악 ends in a consonant, it takes 을.

들으면 comes from 듣다 + -(으)면, which means if/when.

So:

• 듣다 = to listen
• 들으면 = if/when (someone) listens

The reason it becomes 들으면 instead of 듣으면 is that 듣다 is a ㄷ irregular verb.

When a ㄷ irregular verb is followed by a vowel, the ㄷ changes to ㄹ:

• 듣다 → 들어요
• 듣다 → 들으면

This is a very common pattern. Another example:

• 걷다 = to walk
• 걸어요 = walk / am walking

It can mean both, depending on context.

In this sentence, it usually feels more like when or whenever, because it expresses a general result:

• 좋아하는 음악을 들으면 기분이 좋아져요.
• When I listen to music I like, my mood gets better.
• Whenever I listen to music I like, I feel better.

So although -(으)면 is often introduced as if, in real use it can also mean:

• when
• whenever
• if

Here, whenever/when is the most natural interpretation.

Because 기분 is the subject of 좋아져요.

• 기분 = mood / feeling
• 좋아지다 = to become good / to improve

So the sentence is saying that the mood becomes good. That makes 기분 the thing undergoing the change, so it takes 이/가, the subject marker:

• 기분이 좋아져요 = the mood gets better

If you used 기분을, it would sound like mood is the object of some action, which is not what is happening here.

This is an important distinction.

• 좋아요 = is good
• 좋아져요 = becomes good / gets better

So:

• 기분이 좋아요 = My mood is good.
• 기분이 좋아져요 = My mood becomes good / gets better.

In this sentence, listening to favorite music causes a change, so 좋아져요 is more natural than 좋아요.

They are related, but they come from different verbs.

1. 좋아하다 = to like

   • 좋아하는 음악 = music that one likes

2. 좋다 = to be good

3. 좋아지다 = to become good

   • 기분이 좋아져요 = the mood gets better

So even though they look similar, they are not doing the same job:

• 좋아하는 comes from 좋아하다 (to like)
• 좋아져요 comes from 좋아지다 (to become good)

This often confuses learners because English uses like and good/better, while Korean shows a visible connection between these forms.

The subject is omitted, which is very normal in Korean.

The sentence could mean:

• When I listen to music I like, I feel better
• When you listen to music you like, you feel better
• When one listens to music one likes, one’s mood improves

Korean often leaves out subjects when they are obvious from context. So yes, in many situations, English would naturally supply I, but Korean does not need to say it.

Often yes, in practice, but literally it means music that one likes.

So depending on context, it can be understood as:

• music I like
• favorite music
• music that I enjoy

If someone wants to say favorite more explicitly, Korean can also use other expressions, but 좋아하는 음악 is extremely natural and common.

The ending -어요 makes the sentence polite and conversational.

• 좋아져요 is the polite present-style form of 좋아지다
• It is appropriate for everyday speech, neutral conversation, and many written examples for learners

Without the polite ending:

• 좋아져 = casual/informal
• 좋아집니다 = formal polite

So 좋아져요 is a very standard, useful form to learn.

Yes. That is exactly how it usually sounds.

Because of 들으면 (when/if one listens) and the present polite ending 좋아져요, the sentence sounds like a general tendency or repeated experience:

• Whenever I listen to music I like, my mood improves.

It does not strongly sound like a single, one-time event unless the context makes it one.