 
<translate> Iji zaa ajụjụ a, anyị kwesịrị ịma nke a: Ụlọ akwụkwọ sekọndrị ndị dị na Saụt Koria na-akụziri ụmụ akwụkwọ ihe ruo afọ atọ, malite na klas nke mbụ (ndị dị afọ 15 - 17) ruo na nke atọ (ndị dị afọ 17 - 19), ụmụ akwụkwọ na-agụsịkwa akwụkwọ mgbe ha dị afọ iri na asatọ ma ọ bụ iri na itoolu. Azịza ya bụ: afọ 15 ruo afọ 17. <eng> To answer this question, we should know that: High schools in South Korea teach students for three years, from first grade (age 15 -- 17) to third grade (age 17 -- 19), and students commonly graduate at age 18 or 19.
The answer: age 15 -- 17. 