Core Pattern Rule: -(으)ㄴ/는 데다가
This pattern means "on top of that" or "in addition to." It's used to add a second, related piece of information to an existing fact or situation, often to emphasize the combined effect.
Formation
Adjectives: Attach -ㄴ 데다가 to stems ending in a vowel (e.g., 크다 → 큰 데다가) and -은 데다가 to stems ending in a consonant (e.g., 작다 → 작은 데다가).
Verbs: Always attach -는 데다가 to the verb stem, regardless of whether it ends in a vowel or consonant (e.g., 오다 → 오는 데다가, 먹다 → 먹는 데다가).
Past Tense Verbs: Attach -았/었- to the verb stem, followed by -는 데다가 (e.g., 걸렸다 → 걸렸는 데다가). This is often shortened to -ㄴ/은 데다가 in speech (e.g., 감기 걸린 데다가).
있다/없다: These act like verbs, taking -는 데다가 (e.g., 없는 데다가).
Usage
The two clauses connected by this pattern should be related. Typically, they are both positive or both negative, compounding the overall situation.
비 오는 데다가 차도 막혀. / 똑똑한 데다가 친절해. / 돈도 없는 데다가 시간도 없어. / 늦은 데다가 지갑도 안 가져왔어.
Nuance: Compounding the Situation
This pattern does more than just list two facts; it emphasizes how the second fact makes the first one even more intense, whether for better or worse.
Negative + Negative
This is very common for complaining or explaining a difficult situation. The second clause makes things sound worse.
Example: 비싼 데다가 맛도 없어. (It's expensive, and to make matters worse, it doesn't even taste good.)
Positive + Positive
Use this to praise someone or describe a great situation. The second clause adds another layer of positivity.
Example: 날씨도 좋은 데다가 경치도 좋아. (The weather is nice, and on top of that, the scenery is great too.)
The Role of '도'
Notice how the particle 도 (also, too, even) is almost always used in the second clause. It's the key ingredient that reinforces the "on top of that" feeling.
비싼 데다가 맛도 없어. / 똑똑한 데다가 친절해. / 돈도 없는 데다가 빚도 있어. / 날씨도 좋은 데다가 경치도 좋아.
Synonyms & Differences
While -(으)ㄴ/는 데다가 means "in addition to," it has a different nuance from other connectors like -고 and -(으)ㄹ 뿐만 아니라.
vs. -고 (and)
-고 is a simple, neutral connector that just lists facts in sequence. It lacks the emphatic, compounding nuance of -데다가.
-고: 비가 오고 차가 막혀요. (It's raining and there's traffic. - A simple statement of two facts.)
-데다가: 비 오는 데다가 차도 막혀요. (On top of it raining, the traffic is bad too. - Emphasizes the combined negative situation.)
vs. -(으)ㄹ 뿐만 아니라 (not only... but also...)
-(으)ㄹ 뿐만 아니라 is more formal and literary. It's often used in writing or presentations. -(으)ㄴ/는 데다가 is much more common in everyday conversation.
-ㄹ 뿐만 아니라: 그녀는 똑똑할 뿐만 아니라 친절해요. (She is not only smart but also kind.)
-데다가: 그녀는 똑똑한 데다가 친절해요. (She's smart, and on top of that, she's kind.)
방이 작은 데다가 어두워요. / 이 식당은 가격이 쌀 뿐만 아니라 맛도 좋아요. / 사장님은 무서운 데다가 일도 많이 줘요.
Politeness & Formality
The pattern -(으)ㄴ/는 데다가 itself is neutral. The overall politeness of your sentence is determined by the final verb ending.
Casual Language (반말)
To speak casually with friends, family, or those younger than you, end the sentence with endings like -아/어 or -야.
Example: 배고픈 데다가 졸려. (I'm hungry, and on top of that, sleepy.)
Polite Language (해요체)
For standard polite conversation, use the -아요/어요 or -예요/이에요 endings. This is the most common form you'll use in daily life with colleagues, acquaintances, or elders.
Example: 배고픈 데다가 졸려요. (I'm hungry, and on top of that, sleepy.)
못생긴 데다가 성격도 나빠. / 못생긴 데다가 성격도 나빠요. / 잘생긴 데다가 부자야. / 잘생긴 데다가 부자예요.