better words are green corrections are red

can you help me with the grammar problem~? :(

Relationships between friends in university are too shallow, so it’s hard to make real friends. Our whole lives are changing because of the difference between university and high-school students‘s lifestyle. University students are more free than before cause they are adults now. So all the things that we do and all the places that we go are totally changing. According to these huge alteration, our relationship between friends are changed too. Relationships in university are more light and superficial than before. It's because of these several reasons. First, in contrast to high school, students don‘t have any fixed timetable, so the lunch times and relaxing times are all different between them. So, students don‘t eat and relax together. Second, students are usually doing a part-time job or tutoring, so they spend less time in university. Even after all of their classes, they don‘t have time to get along with each other.
To solve this problem, joining particular club activity, which students are interested in could be great solution. Through club activity they can find real friend whose interest filed is same with them. ---------------------------------------------------

I think you did a good job! The biggest problem was singular/plural (one vs many) use of "s" and "is/are". 

So vs Therefore:

Therefore is very formal, and used for university papers and other very formal situations. So is acceptable in most situations (including some formal situations).