An English conversation school — an institution or school focused on teaching conversational English (often called an English conversation school or 'eikaiwa').
私は英会話学校に週に二回通っている。
I attend an English conversation school twice a week.
英会話学校ではネイティブ講師が担当するクラスが人気だ。
Classes taught by native teachers are popular at English conversation schools.
仕事のために英会話学校でビジネス英語を学んだ。
I learned business English at an English conversation school for work.