The school's policy included a proviso that all students must attend a minimum of 90% of classes.
学校的政策包括一个附文，即所有学生必须至少出勤90%的课堂。
Before signing the agreement, the teacher added a proviso about the right to modify the curriculum.
在签署协议之前，老师增加了一个关于修改课程权利的附文。