be enrolled in 招收（注意，此用法很特別，做 enroll 的不是人，而是組織或事件
字典裡的例句
加入：We enrolled in the history course
使加入：They enrolled their children in a private school.
招收：The college enrolls about 25,000 students.
關代省略，意義不同！
enroll in 參加（正常的分詞構句
be enrolled in 招收（此例句還原變成： students who are enrolled in…，所以要翻成「招收」，若使用 students who enroll in…，來表達「加入」也是可以的，不過意思就會不同。