yageul meokgo naseo momi jom johajyeosseoyo.

Yes, 먹다 literally means to eat, but in Korean it is also the normal verb for taking medicine by mouth.

So:

• 약을 먹다 = to take medicine
• not just to eat medicine

This is one of those very common Korean usages that does not match English word-for-word.

A few related expressions:

• 약을 먹어요 = take medicine
• 비타민을 먹어요 = take vitamins
• 감기약을 먹었어요 = I took cold medicine

If the medicine is an injection, Korean would use a different verb, such as 주사를 맞다.

-고 나서 means after doing something.

So:

• 먹고 나서 = after taking/eating

It shows that one action happens first, and then the next thing happens afterward.

In this sentence:

• 약을 먹고 나서 = after taking medicine
• 몸이 좀 좋아졌어요 = my body/condition got a bit better

So the order is:

1. take the medicine
2. then feel better

It is a very common pattern:

• 밥을 먹고 나서 공부해요. = After eating, I study.
• 집에 가고 나서 쉬었어요. = After going home, I rested.

Yes. Both can connect actions, but -고 나서 more clearly emphasizes after that or once that is finished.

Compare:

• 약을 먹고 잤어요. = I took medicine and slept.
• 약을 먹고 나서 잤어요. = After taking medicine, I slept.

The second one sounds more clearly sequential. It highlights that the first action happened before the second.

So in your sentence, 먹고 나서 strongly suggests:

• first the medicine was taken,
• then the condition improved afterward.

Here, 몸 is the subject of 좋아졌어요.

• 몸이 좋아졌어요 = the body/physical condition got better

The verb 좋아지다 means to become good / to improve / to get better, and the thing that improves is marked with 이/가.

So:

• 몸이 좋아졌어요 = my body/condition improved
• not 몸을 좋아졌어요, which would be ungrammatical

In Korean, change-of-state verbs like 좋아지다, 나빠지다, 커지다, 작아지다 usually take the thing changing as the subject.

Literally, yes, it is something like the body became good/better, but naturally it means:

• I felt physically better
• my condition improved
• my body felt better

In Korean, 몸 often refers not just to the physical body as an object, but also to one’s physical condition.

So 몸이 좀 좋아졌어요 is a natural way to say that your physical state improved.

좀 literally means a little / somewhat, but in real Korean it often has a softening or natural-sounding effect.

In this sentence:

• 몸이 좀 좋아졌어요 = my condition got a bit better

It suggests partial improvement, not a dramatic recovery.

Compare:

• 몸이 좋아졌어요. = I got better / my condition improved.
• 몸이 좀 좋아졌어요. = I got a bit better / I feel somewhat better.

So 좀 makes the statement more modest and natural.

Good question. These two forms are related but not the same.

• 좋았어요 = was good
• 좋아졌어요 = became good / got better / improved

Here, 좋아지다 is made from:

• 좋다 = to be good
• -아지다 = to become

So:

• 좋아지다 = to become good, to improve
• 좋아졌어요 = became better, improved

Because the sentence talks about a change after taking medicine, 좋아졌어요 is the right choice.

In Korean, when verbs are linked in a clause like this, the tense is often shown only in the final verb.

So:

• 약을 먹고 나서 몸이 좀 좋아졌어요

already tells us the whole event happened in the past.

The earlier action, 먹고 나서, is understood as happening before the final past-tense result.

If you want, Korean can sometimes mark the earlier action more explicitly in other structures, but here it is completely normal to leave 먹다 unmarked and put the tense only on the final verb.

Yes, the subject is omitted, which is very common in Korean.

From context, this sentence usually means:

• I felt a bit better after taking medicine
• or possibly he/she/they felt a bit better after taking medicine

Korean often leaves out subjects when they are already understood from the situation.

So even though the sentence says:

• 몸이 좀 좋아졌어요 = the body/condition got a bit better

the person is understood from context.

Each word gives a different nuance:

• 몸 = body, physical condition
• 기분 = mood, feelings
• 상태 = condition, state

So:

• 몸이 좋아졌어요 = my physical condition improved
• 기분이 좋아졌어요 = my mood improved / I felt happier
• 상태가 좋아졌어요 = my condition improved

Because the sentence involves taking medicine, 몸이 좋아졌어요 naturally focuses on physical recovery.

Yes, that is possible.

Compare:

• 약을 먹고 나서 몸이 좀 좋아졌어요.
• 약을 먹은 후에 몸이 좀 좋아졌어요.

Both mean roughly After taking medicine, I felt a bit better.

Nuance:

• -고 나서 is very common in everyday speech and feels very natural for sequencing actions.
• -은 후에 sounds a bit more formal or written.

So for normal conversation, 먹고 나서 is often the more natural choice.

좋아졌어요 is in the standard polite style, often called 해요체.

That makes the whole sentence polite and appropriate for many everyday situations.

Compare:

• 좋아졌어요 = polite
• 좋아졌어 = casual/informal
• 좋아졌습니다 = formal polite

So depending on who you are speaking to, you could say:

• 약을 먹고 나서 몸이 좀 좋아졌어. = casual
• 약을 먹고 나서 몸이 좀 좋아졌어요. = polite
• 약을 먹고 나서 몸이 좀 좋아졌습니다. = formal

It suggests that the improvement happened after taking the medicine, and in context it often implies a connection, but grammatically -고 나서 mainly marks sequence, not strict cause.

So the sentence means:

• after taking the medicine, the body felt a bit better

In real conversation, listeners will usually understand that the medicine likely helped. But the grammar itself is more about what happened next than directly saying because of the medicine.

If you wanted to emphasize cause more strongly, Korean could use other expressions, but this sentence already sounds very natural for everyday use.