Learn Hardcore Korean: chingurang doseogwaneseo hangugeoreul gongbuhaeyo. - I study Korean at the library with a friend.

Comitative (with): 친구랑 공부해요 = I study with a friend.
Coordinating (and): 친구랑 선생님 = friend and teacher. In this sentence, it means with.

What’s the difference between 랑/이랑, 하고, and 와/과?

랑/이랑: Casual, common in speech. 이랑 after a consonant (e.g., 책이랑), 랑 after a vowel (e.g., 친구랑).
하고: Neutral and widely used in speech; okay in semi-formal contexts.
와/과: More formal/written. 와 after a vowel (e.g., 친구와), 과 after a consonant (e.g., 책과). All mean either “and” or “with” depending on context.

Do I need 같이 to mean “together,” as in 친구랑 같이?

친구랑 already implies “with,” which often suggests “together.”
Adding 같이 or 함께 makes “together” explicit or emphatic: 친구랑 같이 공부해요.
Both versions are natural; 같이 is optional emphasis.

Why is it 도서관에서 and not 도서관에?

에서 marks the location where an action happens: 도서관에서 공부해요 (I study at the library).
에 marks destination or static location: 도서관에 가요 (I go to the library), 도서관에 있어요 (I am at the library). So studying (an action) needs 에서.

Is 도서관에 한국어를 공부해요 acceptable?

No. For actions like studying, use 에서: 도서관에서 한국어를 공부해요 is natural.

Do I have to use the object particle 를 in 한국어를?

It’s correct and clear to include 를: 한국어를 공부해요.
In casual speech, many omit it if the object is obvious: 한국어 공부해요.
In writing or when clarity matters, keep 를.

What’s the default word order? Can I move words around?

Korean is flexible, but the verb stays at the end. All of these are natural:

친구랑 도서관에서 한국어를 공부해요. (neutral)
도서관에서 친구랑 한국어를 공부해요. (slight emphasis on place)
한국어를 친구랑 도서관에서 공부해요. (emphasis on the object) Particles carry the roles, so order can shift for nuance.

Who is the subject here? How do I say “I” explicitly?

The subject is omitted and understood as I from context. To say it explicitly:

저는 친구랑 도서관에서 한국어를 공부해요. (polite/formal “I”)
나는 친구랑… (casual “I”) You can also say 우리는 for “we” if appropriate.

Why 공부해요 and not 공부합니다 or 공부해?

They’re different politeness levels:

공부해요: Polite, neutral, most common in everyday speech.
공부합니다: Formal/polite, presentations, news, formal writing.
공부해: Casual/banmal, with close friends or younger people.

Can I say 공부를 해요 instead of 공부해요?

Yes. Both are natural:

한국어를 공부해요 and 한국어 공부를 해요 mean the same.
The version with 를 on 공부 can slightly emphasize the action word: 공부를 열심히 해요.

What’s the difference between 공부하다 and 배우다?

공부하다: to study (self-directed work, reading, exercises).
배우다: to learn (being taught by someone). So at the library, 한국어를 공부해요 is most typical. Use 한국어를 배워요 when focusing on learning from a teacher/course.

Is 친구랑 singular or plural? How do I say “with friends”?

Korean often leaves number unspecified. 친구랑 could be “with a friend” or “with friends.” To be explicit:

Singular: 친구 한 명이랑…
Plural: 친구들이랑… or 친구들하고…

Any pronunciation tips for this sentence?

친구랑: as written [친구랑].
도서관에서: liaison makes it sound like [도서과네서] (the final ㄴ of 관 links into 에서).
한국어를: liaison makes 한국어 sound like [한구거], so overall [한구거를]. Natural speech links syllables smoothly; don’t pause between words.

How do I say it in the past, future, or negative?

Past: 친구랑 도서관에서 한국어를 공부했어요.
Future/intention: … 공부할 거예요.
Negative: … 공부 안 해요 or … 공부하지 않아요.

How can I add emphasis with topic markers?

Emphasize place: 도서관에서는 한국어를 공부해요. (as for the library, I study there)
Emphasize object: 한국어는 도서관에서 공부해요. Topic markers (은/는) shift focus/contrast.

Is there a difference between 한국어 and 한국말?

한국어: more formal/academic (Korean language).
한국말: more colloquial (Korean speech/words). Both are fine in everyday conversation.

What about spacing: 공부해요 or 공부 해요?

When 하다 is verbalized, it combines: 공부해요.
If you use an object marker on 공부, write separately: 공부를 해요.

Can 에서 contract to 서, like 도서관서?

In casual speech, yes: 도서관서. In standard writing or careful speech, use 에서. You’ll also often see 어디서 instead of 어디에서.

When do I use 랑 vs 이랑?

After a vowel: 친구랑, 엄마랑.
After a consonant: 책이랑, 형이랑. Many speakers also use 랑 widely in speech, but the above is the standard pattern.

Can 랑 also just mean “and” for lists?

Yes. It coordinates nouns: 책이랑 노트 (books and a notebook). In this sentence, it’s the comitative “with.”

How do I ask “Who are you studying with?” or “Where do you study Korean?”

Who with: 누구랑 공부해요? / 누구하고 공부해요? / 누구와 공부해요? (increasing formality)
Where: 어디에서 한국어를 공부해요? (casual contraction: 어디서…)

Is 친구랑 도서관에서 the only order? What about 도서관에서 친구랑?

Both are fine:

친구랑 도서관에서… (neutral)
도서관에서 친구랑… (slight place-first emphasis) Particles make the roles clear, so choose based on what you want to highlight.