Learn Hardcore Korean: jigeum dongryowa yaegi jungieyo. - I am talking with a colleague now.

회의 중이에요. = I’m in a meeting.
식사 중이에요. = I’m eating (in the middle of a meal). You’ll also see the verbal version V-는 중이다, e.g., 얘기하는 중이에요.

How is 얘기 중이에요 different from 얘기하고 있어요?

Both mean “I’m talking,” but:

얘기 중이에요 highlights the state of being currently engaged in the activity; it sounds a bit more formal/neutral and is common for statuses or excuses.
얘기하고 있어요 is the progressive form and is the most straightforward way to say you’re actively doing it now. In everyday conversation, both are fine.

Why is there no subject like 저는?

Korean often drops the subject when it’s obvious from context. You can add it for clarity or emphasis:

저는 지금 동료와 얘기 중이에요.

What does 와 in 동료와 mean, and why not 과?

와/과 is a particle meaning “with” (comitative) or “and” (linking nouns).

Use 와 after a vowel (동료 + 와).
Use 과 after a consonant (친구 + 과). Spoken alternatives:
More casual: 랑/이랑 (동료랑)
Very common/neutral in speech: 하고 (동료하고)

Do I need to add 같이 (“together”) after 와?

No. 와/랑/하고 already mean “with.” Adding 같이/함께 just emphasizes doing it together:

동료와 같이 얘기 중이에요. (a bit more emphatic)

Is 동료 singular or plural here?

Unmarked nouns in Korean don’t force singular or plural. 동료 could be one or multiple colleagues. If you want to stress plural, say 동료들(과/랑) or use a number:

동료들과 얘기 중이에요.
동료 두 명과 얘기 중이에요.

Is 얘기 the same as 이야기?

Yes. 얘기 is the very common shortened form of 이야기, and both are standard. As verbs:

얘기하다 / 이야기하다 = to talk, to chat, to tell

What’s the correct spacing: 얘기중이에요 or 얘기 중이에요?

Write 얘기 중이에요. 중 is a bound noun, so you leave a space before it. You then attach 이에요 to 중 with no space:

Correct: 얘기 중이에요
(Often seen in casual texting but nonstandard): 얘기중이에요

Why is it 중이에요 and not 중예요?

The copula alternates as 이에요/예요:

After a final consonant: 이에요 (중 ends with ㅇ → 중이에요)
After a vowel: 예요 (학생 → 학생이에요 because 학생 ends with ㅇ? Careful!) Examples:
책이에요 (책 ends with a consonant)
바나나예요 (바나나 ends with a vowel) So here, 중 ends with a consonant, so use 이에요.

How do I make this more formal or more casual?

Formal polite: 지금 동료와 얘기 중입니다.
Plain casual: 지금 동료랑 얘기 중이야.
Honorific (subject is someone you respect): (사장님은) 지금 동료와 얘기 중이세요.

Can I just say 지금 동료와 얘기해요?

You can, but the plain present (해요) often sounds habitual or general. To clearly mean “right now,” 얘기하고 있어요 or 얘기 중이에요 is more natural:

지금 동료와 얘기하고 있어요.
지금 동료와 얘기 중이에요.

If I mean I’m on the phone, should I use a different word?

Yes, use 통화 for calls:

지금 동료와 통화 중이에요. = I’m on a call with a coworker right now. Signs/buttons often use 회의 중, 통화 중, 부재중.

How do I say “with my coworker”?

Add a possessive or a descriptor:

제 동료와 (my coworker; humble)
회사 동료와 (coworker from work)
우리 팀 동료와 (coworker on my team)

Can I move 지금 around?

Yes. Common placements:

지금 동료와 얘기 중이에요. (very natural)
동료와 지금 얘기 중이에요. (also fine; focuses “now” nearer the verb) Avoid separating elements too much; keep 지금 close to the predicate or the relevant phrase.

What’s the difference between 중, 동안, and 중에?

중(이다): “in the middle of” (ongoing state) → 회의 중이에요.
동안: “for/during (a span of time)” → 회의 동안 조용히 있었어요.
중에: “during/among (within a period or set)” → 회의 중에 질문이 있었어요. / 친구들 중에 한국인은 없어요.

How do I negate it or change the tense?

Negative: 지금 동료와 얘기 중이 아니에요.
Past: 아까 동료와 얘기 중이었어요.
Reason clause: 지금 동료와 얘기 중이라서 나중에 연락드릴게요.

Does 와 mean “with” or “to” here? What if I want “talk to someone”?

Here 와 is “with” (comitative): 동료와 얘기 = talk with a coworker.
To emphasize direction “to,” use 에게/한테 with 얘기하다/말하다:

동료에게 얘기했어요. / 동료한테 말했어요. (talked/said to a coworker)