This is the 542nd most frequent Korean word.
사용한
"Used" or "utilized."
In this sentence, '사용한' is used in its function as an adjective to describe '기계를' (machines). It indicates that the machines being referred to utilize old technology.
그는 오래된 기술을 사용한 기계를 선호합니다.
He prefers machines utilizing old technology.
Here, '사용한' serves as an adjective modifying '도구를' (tools), specifying that the tools were employed in working on the project.
이 프로젝트에 사용한 도구를 다시 마련해야 합니다.
We need to procure again the tools used for this project.
In this example, '사용한' is an adjective describing '방법은' (method), denoting the method that was utilized yesterday.