do you think it should be "in"...maybe...to my opinion...."that" is more suitable
Yes! I agree. It's like this:
There are several reasons that contribute to this phenomenon.
As you continue to practice English, use short sentences instead of long, complex ones:
With the revolutionary change in the last half century, the entire human society has experienced great progress in varied respects beyond our wildest expectatio
ns . Meanwhile, the problems of...
And I'll make a small change to the end, too:
In brief, only when individuals develop themselves in a healthy way and hold strong moral values can the antisocial behaviors be decreased to some extent. Furthermore, governments should ensure the economic environment can be developed in a healthy way.
stylePractice these corrections. :-) You write very clearly... keep practicing!