One suggestion I have is about the phrase "university classes". It doesn't seem to be very smooth sounding to me. "university students attending classes" is much more natural and clear than "students attending university classes". (Just as we'd prefer to say "teachers doing a good job" rather than "people doing a good teacher job") In the US, college is interchangeable with university in many contexts, and may work better here too. Anyway, here's my attempt at "impressive" alternatives. 1.It is easy to grasp the importance of attending university classes. => (Formal) It doesn't take much thought to realize class attendance is imperative for university students. => (Informal) It's a no-brainer that university students ought to attend classes. 2. Most students place importance on attending university classes. => Most university students consider class attendance too important to neglect.

1. It is easy to grasp the gravity of attending university classes. The importantance of attending university classes is not lost on the students 2. Attending university classes is held in high regards by most students. :)

Not sure what you meant by impressive, but I wrote something down 1. It is clear that attending class is important 2. Most students think that attending class is important. *Assuming the "university" part is supplied through context

It is obvious that going to university is different from going to university classes. You can be a university student and do not go to your classes. When I say going to university classes, you can infer that you go to university too. Yes the subject is students. " it is easy to grasp the importance of attending university classes for students" . Thanks

Does the subject of this sentence have to be students? What context is this in? Also, are you talking about attending the whole of university (as in "going to college") or are you talking specifically about a group of individual classes? (If you mean all of university, the word "classes" is unnecessary and confusing. As for the most impressive alternative to the information given, I would go with "It is apparent to most students that the attendance of university classes is imperative."