Learn Hardcore Korean: byeoge sigyereul georeo dueossjiman sigani jaju teullyeoyo. - I hung a clock on the wall, but it’s often wrong.

걸다 means “to hang,” and the grammatical construction -아/어 두다 indicates performing an action and leaving something in that resulting state. Thus 걸어 두다 literally means “hang up (and leave it).” The form 걸어 두었지만 is the past tense (-어 두었) plus -지만 (“but/though”), so it conveys “I hung it up (and left it), but…”

What is the function of 지만 in 걸어 두었지만?

-지만 is a conjunction meaning “but” or “although.” It connects the first clause (“I hung it up”) with the contrasting result in the second clause (“the time is often wrong”).

Why is 시간이 the subject in 시간이 자주 틀려요, instead of 시계가?

The focus is on the time being wrong, not the clock itself. In Korean, you say 시간이 틀리다 (“time is wrong/off”). If you said 시계가 틀려요, it would sound like “the clock is wrong,” which is less natural when you mean “the clock shows the wrong time.”

What nuance does 틀려요 carry here compared to saying 안 맞아요?

틀리다 means “to be incorrect” or “not match the correct value.” When talking about clocks, 시간이 틀리다 means the displayed time doesn’t match the real time. You could also say 시계가 안 맞아요 (“the clock doesn’t match”), which is very similar in meaning but slightly more casual.

Can I use 달아 두었지만 instead of 걸어 두었지만 for hanging a clock?

Yes. 달다 (“to attach/hang”) can also be used with clocks, so 달아 두었지만 works fine. 걸다 is more common for pictures and frames, but both verbs are acceptable here.

Why is the hanging action in the past (걸어 두었지만) while the time being wrong is in the present (틀려요)?

Because the clock was hung up at a specific point in the past (completed action), whereas the problem of the time being wrong is an ongoing condition in the present.

What role does the adverb 자주 play in 시간이 자주 틀려요?

자주 means “often” or “frequently.” It modifies 틀려요, indicating how frequently the displayed time is incorrect.

Could I say 걸어 놓았지만 instead of 걸어 두었지만, and is there any difference?

Yes. -아/어 놓다 and -아/어 두다 both convey doing something and leaving it in that state. 걸어 놓았지만 and 걸어 두었지만 are essentially interchangeable here, with no significant difference in meaning.