baekhwajeom maejangeseo ibeo bonikka jeongmal pyeonhaesseo.

입어 보다 means to try on clothes.

• 입다 = to wear
• 보다 after another verb often means to try doing something

So 입어 보다 literally looks like wear and see, but in natural English it means try on.

In this sentence, it refers to trying on some clothing item at the store.

Because 입어 보니까 means after trying it on / when I tried it on, I found that...

This is different from just 입으니까, which would more literally mean because/when I wear it.

The part -아/어 보다 adds the idea of trying something out. So:

• 입으니까 = when/because I wear it
• 입어 보니까 = when/because I tried wearing it

That 보다 is important because it shows this was a test or trial experience.

Here, -니까 connects the two parts of the sentence and gives a meaning like:

• when I tried it on
• after trying it on
• because I tried it on

In this sentence, it has a very natural discovery/result feeling:

• 입어 보니까 정말 편했어
• When I tried it on, it was really comfortable

So -니까 is not just simple cause. It often suggests I did X, and then I realized/found out Y.

에서 marks the place where an action happens.

Here, the action is 입어 보니까 (trying it on), so 백화점 매장에서 means at/in the department store shop section.

Compare:

• 에 = location, destination, existence
• 에서 = place where an action occurs

Since trying on clothes is an action, 에서 is the natural choice.

• 백화점 = department store
• 매장 = store floor, sales area, shop section

So 백화점 매장에서 means something like:

• at the department store shop
• in a department store sales area
• at the department store counter/section

It may sound slightly repetitive in English, but in Korean it is natural. It gives a more specific setting than just 백화점에서.

Yes. Korean often leaves out things that are obvious from context.

In 입어 보니까 정말 편했어, the thing being tried on is not stated, but it is understood to be some clothing item, such as:

• a shirt
• pants
• a jacket
• shoes, depending on context

In English, we often need to say it or name the item. In Korean, if everyone already knows what item is being discussed, it is commonly omitted.

The subject is also omitted.

Grammatically, 편했어 means was comfortable, and the thing that was comfortable is the clothing item that was tried on.

So the implied meaning is:

• I tried it on at the department store, and it was really comfortable.

Not:

• I was really comfortable in a broad general sense

It is the item being evaluated as comfortable when worn.

편했어 is the past form of 편하다 (to be comfortable).

It is used because the speaker is talking about how it felt at the time they tried it on.

So the nuance is:

• I tried it on, and it felt really comfortable.

Even if the clothing is still comfortable now, Korean often uses the past tense here because the speaker is reporting a past experience or impression.

편했어 is in the casual/informal polite-neutral style, often used with:

• friends
• people younger than you
• diary-style narration
• casual spoken storytelling

The dictionary form is 편하다.

Some other possible endings would be:

• 편했어요 = polite
• 편했습니다 = formal
• 편했어 = casual

So this sentence sounds like relaxed spoken Korean.

Here 정말 means really or truly and adds emphasis.

• 편했어 = it was comfortable
• 정말 편했어 = it was really comfortable

It makes the reaction sound stronger and more personal. In spoken Korean, 정말 is very common for giving genuine emphasis.

Yes, that is a very natural translation.

A few possible translations are:

• I tried it on at the department store, and it was really comfortable.
• When I tried it on at the department store, it was really comfortable.
• After trying it on at the department store, I found it really comfortable.

The best English translation depends on how explicitly you want to show the nuance of -니까, but all of these are reasonable.

That would also be possible, but the nuance changes a little.

• 입어 보니까 = after trying it on, I found/realized...
• 입어 봤는데 = I tried it on, and... / but...

-보니까 often emphasizes discovery through experience.

So 입어 보니까 정말 편했어 sounds especially natural when the speaker is reporting what they learned from trying it on.

It is built in steps:

1. 입다 = to wear
2. 입어 = connective form of 입다
3. 입어 보다 = to try wearing / to try on
4. 입어 보니까 = when/after trying it on

So the pattern is:

• Verb stem + 아/어 보다 = try doing
• Verb + -니까 = when/because

Together, it gives the idea:

• when I tried doing it
• after trying it, I found that...