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being attached (to); being affiliated (to); belonging (to); going with
attached school; affiliated school
大学の附属病院で診察を受けてきました。
I was examined at the university hospital.
彼女は有名な附属高校に通っている。
She attends a famous affiliated high school.
この研究所は大学に附属している。
This research institute is affiliated with the university.