فعاليات إشراك الخريجين

alumni is defined in Cambridge Dictionary:
men and women who have completed their studies, esp. at a college or university:

I think here he meant the engagement of graduates at events that may be gathering, activities, etc.
Engagement leads to giving, and one of the best ways to engage alumni is through in-person events. Whether your school’s events are large or small, frequent or rare, there are some great ways to ensure that you are engaging your alumni base.

I think events here may be أنشطة /فعاليات/ أحداث/ تجمعات

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