"Grade" refers to the year of admission and "session" refers to the year of graduation. For example, you graduated from high school on 20 15 and entered the university. So you are a graduate of 20 15 in high school and a freshman of 20 15 in college. If you have a four-year undergraduate course, you are a graduate of class 20 19.

1. The "grade" of the school means "grade" and can also be extended to "grade". 20 18 is accepted as "grade 20 18", also called "grade 20 18" or "grade 20 18".

2. One meaning of the word "session" in school is "limit", which can also be extended to "arrive" or "arrive". The word "then" means that time is up. The meaning of quantity is derived from "to", which is used for regular things and represents a complete process, which is roughly equivalent to "time" or "period". Students' graduation is only the completion of a learning process, so students who graduate from 20 18 should be graduates of 20 18, that is, graduates of 20 18.

3.？ The meaning of "period" and "session" in school is similar. For example, Huangpu Phase I, Beijing Normal University MBA Phase I and so on.