Say:
He’s an alumnus of UI (not, alumni).
A male who graduated from a school is an alumnus; a female is an alumna and two or more persons are alumni).
I can hear you (not, I am hearing you). ‘Hearing’ can be used for a court session: The court is hearing his case this morning.
This is the most important criterion for membership (not, criteria). ‘Criteria’ is plural: You must meet the criteria for membership.
GAB