Pattern V-고 싶다 To want to V, Would Like to V

Verb (V)-고 싶다, conjugated as V-고 싶어(요), means "to want to V" and is a common pattern in Korean as it is in English. Replace V in V-고 싶다 with an action (processive) verb by taking its dictionary form and replacing '' with ''. 

The pattern V-고 싶다:

  • can only be used with action (processive) verbs, such as 가다, 먹다, or 자다; it cannot be used with adjectives (descriptive verbs) such as 춥다, 필요하다, or 예쁘다
  • can only be used when the subject is yourself, or when you are directly asking a question to somebody else; for any other case, use V-고 싶어하다.
  • cannot be used with Noun (N)-이다; use N이/가 되다 instead ("I want to become N").
  • can be combined with past and future markers. These markers go after 싶다 and not after V; for example, "하고 싶었어요" (O) & "하고 싶을거예요" (O), and not "했고 싶어요" (X) & "할고 싶어요" (X) or "했고 싶었어요" (X) & "할고 싶을거예요" (X). Like in English, using the pattern V-고 싶다 in the future tense is not common (e.g., "I will want to see you; 내가 널 보고 싶을거야").
  • cannot be used with 못 (as in 못하다 cannot do).

When using honorifics with V-고 싶다:

  • place the honorific marker -- in the conjugation of 싶다: V-고 싶으세요/V-고 싶어하세요.
  • if V is a verb with an honorific equivalent, use the honorific form instead. E.g., 드시고 싶어하세요 (O) instead of 먹고 싶어하세요 (X).

Examples

Informal and Semi-Polite (Without Honorifics)

나는 이 책을 갖고 싶어.
I want to have this book (반말).
저는 이 책을 갖고 싶어요.
I want to have this book (semi-polite)
이 음반을 듣고 싶었는데 잃어버렸어(요).
I wanted to listen to this album but I lost it.
Note that the verb 듣다 "to listen" conjugates to 들어(요); however, as mentioned above, this pattern uses the dictionary form 듣다 and replaces '다' for '고', resulting in '듣고' (O) and not '들고' (X).
준형이 육회를 먹고싶어(요)?
Junhyeong, do you want to eat yukhoe?
광장시장에 가고 싶었는데 못 갔어(요).
I wanted to go to Gwangjang Market but I could not go.
광장시장에 어제 갔는데 다시 가고 싶어(요).
I went to Gwangjang Market yesterday but I want to go again.
대학을 졸업한 후에 검사가 되고 싶어(요).
I want to become a prosecutor after I graduate from college.
Note the use of "검사가 되고 싶다" (O) rather than "검사 이고 싶다" (X).
미국에 이사한 후에 버거를 매일 먹고싶을 것 같아(요).
After I move to America, I think I will want to eat burgers every day.

Semi-Polite and Polite (With Honorifics)

할아버지께 이 책을 드리고 싶어요.
I want to give this book to my grandfather.
할아버지께서 저한테 이 책을 주고 싶어하세요.
My grandfather wants to give me this book.
In this case, "my grandfather" is the subject; as the subject of the sentence is not yourself and the sentence is not a question, 싶어하다 must be used instead of 싶다.
말씀을 드리고 싶었는데 시간이 부족해서 못 해 드렸어요.
I wanted to tell you (somebody esteemed) something but since we were short on time I couldn't tell you. 
아이스크림을 드시고 싶으세요?
Do you want to eat ice cream? (semi-polite with honorifics)
저는 이 책을 갖고 싶습니다.
I want this book (polite).
This form ending in "-습니다" is uncommon in daily life. Used mostly when speaking in front of crowds (speeches, meetings, broadcast) or in specific work- or family-related functions.
아이스크림을 드시고 싶으십니까?
Do you want to eat ice cream? (polite with honorifics).
As mentioned above, this form is not common in daily life.

Additional Notes

  • Processive verbs can be made from adjectives using the pattern Adj아/어+지다, "to become Adj". For example, 예브다 "to be pretty" becomes 예뻐지다 "to become pretty". Adjectives modified as such can be used with the pattern V-고 싶다 in most cases; for example, "저는 예뻐지고 싶어요," meaning "I want to become pretty".
  • Avoid using in front of V-고 싶다 for negation; as noted in the book Elementary Korean, the longer the verb V is, the worst the sentence will sound. For example, "커피를 안 주고 싶어요, I do not want to give you coffee" sounds relatively better than "커피를 안 떨어트리고 싶어요, I do not want to drop the coffee." Prefer using V-고 싶지 않다: "커피를 주고 싶지 않아요" and "커피를 떨어트리고 싶지 않아요."

See Also