Γειά σου! In fact, the grammatical past perfect tense doesn't exist in Korean language. past perfect tense can be expressed as follows 1) experience of past : V + 본 적이 있다 He wondered if I had been to L.A. before. 그는 내가 전에 LA에 가본 적이 있는지 궁금해 했다. 2) continuing situation of past : V + (았/었)었다 I thought he had been alive until then. 나는 그때까지 그가 살아있었다고 생각했다.(계속) 3) result of past action : V + (았/었)다(treated as simple past) I told my friend I had bought the music CD. 나는 내 친구들에게 내가 음악 CD를 샀다고 말했다.(결과) 4) finished action of past : V + (았/었)었다 I had finished my homework when she called me. 나는 그녀가 나를 불렀을 때 숙제를 끝냈었다.(완료) 5) pluperfect : V + (았/었)던 I lost the umbrella which I had bought the day before. 나는 내가 어제 샀었던 우산을 잊어버렸다.