Want and Can · -고 싶어요, -(으)ㄹ 수 있어요

2. How it works

2.1 Want: verb stem + 고 싶어요

To say you want to do something, remove 다 from the verb and add 고 싶어요. The ending is the same for every verb, whether the stem ends in a vowel or a consonant.

Verb stem + 고 싶어요    →  I want to ...

가다  →  가 + 고 싶어요   →  가고 싶어요
먹다  →  먹 + 고 싶어요   →  먹고 싶어요

The meaning is "I want to go" and "I want to eat". There is no spelling change, so you do not need to think about vowels or consonants here.

2.2 The past and questions: 싶었어요

To say you wanted to do something, change 싶어요 to 싶었어요. The first part stays the same. So 가고 싶어요 becomes 가고 싶었어요, which means "I wanted to go".

In a question, 싶어요 asks about the other person's wish. 뭐 먹고 싶어요? means "What do you want to eat?". So 싶어요 is used for "I" in statements and for "you" in questions.

2.3 Other people: 싶어해요

The form 싶어요 describes your own feeling. For a third person, such as a friend, he, she or they, use 싶어해요 instead. You replace 싶어요 with 싶어해요.

저는 가고 싶어요.           →  I want to go.
친구는 가고 싶어해요.       →  My friend wants to go.

You cannot feel another person's wish directly, so Korean marks it as something you observe. Use this only for the person you are talking about. Do not use it for yourself.

2.4 Can: verb stem + (으)ㄹ 수 있어요

To say you can do something, add ㄹ 수 있어요 or 을 수 있어요 to the stem. The choice depends on the last sound of the stem. A vowel stem takes ㄹ, and a consonant stem takes 을.

Vowel stem      + ㄹ 수 있어요   가다  →  갈 수 있어요
Consonant stem  + 을 수 있어요   먹다  →  먹을 수 있어요

With a vowel stem, ㄹ moves onto the last syllable as a final consonant, so 가 + ㄹ becomes 갈. With a consonant stem, you add the whole syllable 을, so 먹 + 을 gives 먹을.

2.5 ㄹ-stems and the conjugation table

Some verbs already end in ㄹ, such as 만들다 (to make) and 살다 (to live). These stems do not add anything. You just add a space and 수 있어요, so 만들다 becomes 만들 수 있어요.

The -고 싶어요 column never changes its form. Only the ability column needs a rule: ㄹ after a vowel, 을 after a consonant, and nothing extra after ㄹ.

2.6 Cannot: 수 없어요, and the space

To say you cannot do something, replace 있어요 with 없어요. So 갈 수 있어요 (I can go) becomes 갈 수 없어요 (I cannot go). The part before 수 stays exactly the same.

갈 수 있어요.    →  I can go.
갈 수 없어요.    →  I cannot go.

The word 수 is a separate word, so always write a space before it. The correct way is 갈 수 있어요, not 갈수 있어요. The space also appears in romanization: gal su i-sseo-yo.