chinguga sajineul jjigeo jwosseoyo.

가 is the subject marker. It marks 친구 as the person who performed the action.

So in this sentence:

• 친구가 = the friend / my friend (as the subject)
• 사진을 = the photo (as the object)
• 찍어 줬어요 = took it for someone

A learner often compares 가 with 는. Here, 친구가 sounds like it was my friend who did it or simply introduces friend as the subject. If you changed it to 친구는, the nuance would shift more toward as for my friend... or contrast.

The basic verb is 찍다, which literally has meanings like to 찍/press/shoot/mark, depending on context. With 사진, the expression 사진을 찍다 means to take a picture.

So even though English uses take, Korean uses 찍다.

Examples:

• 사진을 찍어요 = take a picture
• 사진을 많이 찍었어요 = took a lot of pictures

This is just the normal Korean expression, so it is best learned as a set phrase: 사진을 찍다.

-아/어 주다 means that someone does an action for someone else. It adds the idea of a favor, kindness, or benefit to another person.

So:

• 사진을 찍었어요 = took a picture
• 사진을 찍어 줬어요 = took a picture for someone

In this sentence, the friend did the action as a favor or for the benefit of someone else, usually me/us/him/her, depending on context.

It is not stated directly, but it is understood from context.

Korean often leaves out words that are obvious to the listener. In this sentence, 찍어 주다 already tells you the action was done for someone, and that person is often omitted if it is clear.

So 친구가 사진을 찍어 줬어요 often naturally means:

• My friend took a picture for me
• or My friend took the picture for us/him/her, depending on context

If you want to say it explicitly, you can add the recipient:

• 친구가 저에게 사진을 찍어 줬어요 = My friend took a picture for me
• 친구가 아이에게 사진을 찍어 줬어요 = My friend took a picture for the child

Not necessarily.

The sentence says the friend took a picture for someone, not specifically of someone.

That is an important difference:

• 사진을 찍어 줬어요 = took a picture for someone
• It does not by itself tell you what or who was in the picture

So the friend may have:

• taken a picture of you,
• taken a picture of your family,
• taken a picture of a building,
• or just handled the camera for you

If you want to say My friend took a picture of me, you would say something like:

• 친구가 제 사진을 찍어 줬어요

Here 제 사진 means my picture/photo.

줬어요 is the contracted form of 주었어요.

Breakdown:

• 주다 = to give
• 주었어요 = past polite form
• 줬어요 = contracted, more natural in everyday speech

Both are grammatically related, but 줬어요 is what you will hear much more often in conversation.

So:

• 찍어 주었어요 = full form
• 찍어 줬어요 = common contracted form

It is past tense and polite speech.

Breakdown:

• 찍어 주다 = to take a picture for someone
• 찍어 줬어요 = did so in the past, politely

This -어요 style is often called informal polite or polite conversational style. It is very common in everyday Korean.

Related forms:

• 찍어 줘요 = present polite
• 찍어 줬어요 = past polite
• 찍어 줬습니다 = past formal polite
• 찍어 줬어 = past casual/informal

Korean often omits possessives like my, your, and his/her when they are obvious from context.

So 친구가 often naturally means:

• my friend
• a friend
• the friend

The exact meaning depends on the situation.

In English, you usually need to say my friend, but in Korean, saying just 친구 is very natural if the listener can easily understand whose friend you mean.

You could say:

• 내 친구가 사진을 찍어 줬어요

But in many everyday situations, just 친구가 sounds more natural and less repetitive.

Learners are usually taught to write it as 찍어 줬어요, with a space, because 주다 is acting like an auxiliary verb after the main verb.

So the standard learner-friendly way is:

• 찍어 줬어요

You may also see 찍어줬어요 in casual writing or everyday use. That does happen. But if you are studying carefully or writing for class, 찍어 줬어요 is the safer form to use.

The basic meaning stays similar, but the nuance changes.

• 친구가 사진을 찍어 줬어요 focuses on the friend as the subject, often answering Who took the picture for you?
• 친구는 사진을 찍어 줬어요 puts friend in the topic position, often giving background or contrast, like As for my friend, they took the picture for me

So:

• 누가 사진을 찍어 줬어요?
  친구가 사진을 찍어 줬어요.
  = Who took the picture for you? My friend did.

But with 는, it can sound more like:

• My friend took the picture, but someone else did something else
• or As for my friend, they took the picture

By itself, 사진 does not clearly show singular or plural. Korean often leaves number unspecified unless it matters.

So 사진을 찍어 줬어요 can mean:

• took a picture
• took the picture

If you want to be clearly plural, you can add more information, such as:

• 사진을 많이 찍어 줬어요 = took a lot of pictures for me
• 사진들을 찍어 줬어요 = took the photos for me
  (though 들 is not always needed and can sound less natural in some contexts)

So in many cases, you understand singular or plural from context rather than from the noun itself.