Can and can’t: -(으)ㄹ 수 있어요 / 없어요

Three things you can do

갈 수 있어요 — I can go. 할 수 있어요 — I can do it. 먹을 수 있어요 — I can eat it.

All three end in 수 있어요. That is the 있어요 you know, “there is”: roughly, “there is a way to go”. In front of 수 the verb ends in ㄹ (갈, 할) or in 을 (먹을). In writing these are three separate words.

수 is pronounced [쑤] in this pattern: [갈 쑤 이써요]. The spelling stays 수.

ㄹ after a vowel, 을 after a consonant

The pattern is written -(으)ㄹ 수 있어요. If the stem ends in a vowel, ㄹ goes underneath it as a final consonant: 가다 → 갈, 만나다 → 만날, 하다 → 할. If the stem ends in a consonant, add 을: 먹다 → 먹을, 읽다 → 읽을.

내일 만날 수 있어요? — can we meet tomorrow? 한국어를 읽을 수 있어요 — I can read Korean. You have built this ㄹ / 을 before: it is the first half of 갈 거예요 and 먹을 거예요.

읽을 is pronounced [일글].

Can’t: 수 없어요

For “can’t”, swap 있어요 for 없어요: 할 수 없어요 — I can’t do it. Nothing else moves.

A new phrase, 매운 음식, spicy food, gives a question you will be asked in Korea: 매운 음식을 먹을 수 있어요? The answer repeats the verb: 네, 먹을 수 있어요, or 아니요, 먹을 수 없어요. English stops at “yes, I can”; Korean has no bare “can” to stop at, so the whole verb phrase comes back.

수 없어요 and 못

매운 음식을 먹을 수 없어요 and 매운 음식을 못 먹어요 mean the same: I can’t eat spicy food. You already know 못. It is shorter and is what people usually say; 수 없어요 sounds a little more deliberate.

On the positive side there is no short partner. “Can” is always -(으)ㄹ 수 있어요.

못 먹어요 is pronounced [몬 머거요].

Help, fix, understand

도와줘요 (도와주다) is “help”. 도와줄 수 있어요? — can you help me? — is a common, gentle way to ask. 고쳐요 (고치다) is “fix”: 컴퓨터를 고칠 수 있어요?

이해해요 (이해하다) is “understand”: 이해할 수 없어요 — I can’t understand it. And 한자 are Chinese characters, which still appear in Korean names, signs and newspapers: 한자를 읽을 수 있어요.

고쳐요 is pronounced [고처요]; 한자 is [한짜].

Stems that already end in ㄹ

만들어요 is 만들다, and its stem 만들 already ends in ㄹ. That ㄹ does the job by itself, so nothing is added: 김밥을 만들 수 있어요 — I can make gimbap.

The same goes for 살다 and 놀다: 살 수 있어요, 놀 수 있어요. You do not need to drill this. Just do not be surprised when no 을 appears after a ㄹ stem.