Sentence Conjunctions 접속부사 and the 그렇다 Pattern

Korean has two completely different machines for connecting ideas, and this group is about the second one. The first machine — connective endings (연결어미) — fuses two clauses inside a single sentence by gluing "-and / -but / -because" onto the first verb's stem (밥을 먹고 자요). The second machine — 접속부사 (conjunctive adverbs), the subject of this group — works across a full stop: a word like 그리고 ("and"), 그래서 ("so"), or 하지만 ("but") stands at the start of a new sentence and links it back to the previous complete one. This page maps the whole set and hands you the key that makes most of them memorizable in one stroke.

What a 접속부사 is

A 접속부사 sits at the very front of a sentence, after the previous sentence's period, and connects the two. It is invariant — it never conjugates, takes no tense, no particle, no politeness marker. All the grammatical action happens on the verbs at the ends of the two sentences; the conjunction just names the relationship between them.

Each conjunction here bridges two finished sentences. 그래서 says the second is a result of the first; 그런데 flags a contrast or shift. Compare this with the connective endings, which would fuse the same ideas into one sentence (비가 와서 집에 있었어요) — same meaning, different packaging. The relationship between these two machines is the throughline of the whole group.

The key: almost every conjunction is 그렇다 + an ending

Here is the insight that turns a scary list of conjunctions into a single pattern. The verb 그렇다 means "to be so / to be that way" — it points back and stands in for the entire previous sentence, like English "it's like that." Attach a connective ending to 그렇다 and you get a conjunction whose meaning is "[the previous thing] being so, …". That is literally what 그래서 is: 그렇다 + the causal ending -아서 = "it being so, therefore." Every conjunction below is built this way, which means each one has an ending twin — the same ending you would use to fuse clauses inside a sentence.

Read any row as a sentence-level version of its ending. 그래서 is -아/어서 across a period; 그러면 is -(으)면 across a period; 그래도 is -아/어도 across a period. Learn the endings and the conjunctions come almost free — and vice versa.

Why the shapes shift: 그렇다 is ㅎ-irregular

You may wonder why it's 그래서 and not ×그렇아서, or 그러면 and not ×그렇으면. The answer is that 그렇- is an ㅎ-irregular stem: its final ㅎ disappears before an ending, and before the vowel -아/어 the stem vowel additionally fuses to 애. So:

• Before a consonant/으-ending, the ㅎ (and any 으) drops: 그렇 + -(으)니까 → 그러니까, 그렇 + -(으)면 → 그러면, 그렇 + -(으)ㄴ데 → 그런데.
• Before -아/어, the ㅎ drops and the vowel becomes 애: 그렇 + -아서 → 그래서, 그렇 + -아도 → 그래도, 그렇 + -아야 → 그래야.

This is the identical pattern you see in the color adjectives (파랗다 → 파래서, 파라면) and in 어떻다 → 어때, 어떠면. Once you recognize 그렇다 as ㅎ-irregular, the 그러-/그래- split stops looking arbitrary.

The parallel 이렇다 / 저렇다 series

그렇다 has two demonstrative cousins built the same way: 이렇다 ("be like this," pointing to something near/just-mentioned) and 저렇다 ("be like that, over there"). They generate their own conjunction-like forms with the same ㅎ-irregular shifts: 이렇 + -아서 → 이래서 ("this being so"), 저렇 + -아서 → 저래서 ("that being so"). These are less frequent than the 그- series but common in speech, especially 이래서 when the reason was just laid out.

The exceptions: 하지만 and 그리고

Two of the most common connectors are not built from 그렇다, and it is worth flagging them so you do not go looking for a nonexistent pattern:

• 하지만 ("but") comes from the verb 하다 ("to do/say") + -지만, roughly "though (one) says so." It is the everyday "but" that opens a contrasting sentence — the sentence-level cousin of the ending -지만.
• 그리고 ("and / and then") is a frozen form and does not decompose into 그렇다 + ending. Its ending twin is the plain -고, but the shape itself is just memorized.

Spoken contractions

In casual speech the longer 그러-/그런- conjunctions get clipped. You will hear these constantly in conversation and see them in texting; they are informal and should stay out of formal writing:

The reframe: Korean opens fewer sentences than English

Here is the habit that most needs breaking. English is comfortable writing lots of short sentences bridged by "And… So… But…". Korean strongly prefers to chain clauses with endings and start fewer new sentences. Where an English writer produces "I was tired. So I went home," natural Korean fuses it into one clause: 피곤해서 집에 갔어요. The conjunction 그래서 is held in reserve for a deliberate fresh sentence — a reset, an emphasis, a new breath — not for every "so."

So for any two ideas you want to connect, ask first: can I fuse them with an ending? Usually you can, and it will sound more native. Reach for the sentence-opening conjunction only when you genuinely want two separate sentences. The single most common error learners make in this whole area is stringing everything together with 그리고 — because English loves "and" — where a fused -고 or -아서 would read far better. That error gets its own full treatment on the 그리고 page.

Common Mistakes

1. Opening every sentence with 그리고 (English "and-itis"). Chaining short sentences with 그리고 sounds choppy and childish; fuse them with endings instead.

2. Doubling the link — a conjunction on top of its own ending. Don't mark the relationship twice; pick the fused ending or the opening conjunction, not both.

3. Using 그리고 where you mean "and so" (cause). English "and" often hides a "so"; Korean 그리고 never carries cause. Use 그래서.

4. Using formal 그러나 / 그러므로 in casual conversation. These belong to writing and speeches; in everyday speech they sound stiff. Use 그런데/근데 and 그래서/그러니까 instead.

Key Takeaways

• 접속부사 (conjunctive adverbs) open a new sentence and link it to the previous one — as opposed to 연결어미 endings, which fuse clauses inside one sentence.
• Almost every conjunction = 그렇다 ("be so") + a connective ending, so each has an ending twin: 그래서 ↔ -아/어서, 그러면 ↔ -(으)면, 그래도 ↔ -아/어도.
• 그렇다 is ㅎ-irregular, which is why the shapes split into 그러- (before consonant/으) and 그래- (before -아/어).
• 하지만 (from 하다) and 그리고 (frozen) are the odd ones out — not 그렇다-derived.
• Casual speech clips them: 근데 < 그런데, 그니까 < 그러니까, 그럼 < 그러면.
• Korean opens fewer sentences than English — fuse ideas with endings first (피곤해서 갔어요); save the conjunction for a deliberate new sentence, and don't over-use 그리고.