同学关系证明翻译求助，急！

前面的都翻译了，但是我想提醒下，届是指毕业的年份，而不是入学的年份。
We hereby certify that the following persons, belonged to class 3, all graduated from our high school in 1977.
（belonged to class 3 做插入语。指出都是3班的，而且都是1977年毕业的，就可以知道是同班同学了。）
希望我的回答您能满意，谢谢！

I certify that the following staff is a 1977 high school graduates of our school, the same high school (3) graduate students in the class.
Help with the translation, not very grateful!

兹证明以下人员属我校一九七七届高中毕业生，同是高中（3）班毕业的同学。
I certify that the following persons are high school graduates of the school one hundred ninety-seven seventh, the same high school (3) class graduates.

We hereby certificate that the following persons are graduates of our high school,Class 3 enrolled in 1977.

This proof following 1977 session of personnel in our school, high school graduates with high school (3) class graduates students.