In spite of the fact that youngsters in the past usually left their parents when marrying, today they tend to do so in time of studying or working in other places. Although this trend has its own merits and demerits, I think the advantages outweigh the disadvantages. (The intro is so good, but I don't agree with ur thesis sentence.)
One of the main drawbacks of leaving parents is the impact of new circumstances on young people. In most cases they find new conditions harsh and undesirable. And considering the lack of supervisory already carried out by parents these circumstances may lead to doing wicked things such as drug abuse. The high rate of addiction among those young people proves it. Moreover, they also suffer from homesickness. This might face abroad young people with depression remaining many years with them.
On the other hand, there are some benefits in studying and working somewhere else. One of the main advantages would be gaining independence. Living away from home, children have to make most of daily decision by themselves. This would lead to think and act independently. And having more interacted with people would increase their social skills. Meanwhile, it is very likely to see that those children are more self-disciplined than others as they have to do their daily chores such as laundry, shopping and cleaning house.
To sum up, I think working and studying in different places benefit young people in terms of both enhancing independence and responsibility, although they might encounter with some problems such as loneliness and the risk of falling in illegal activities.
I read the essay, its really great. No grammar mistakes at least I don't find any. The cohesion is strong and the luxical is sufficient. Idea is great. I don't now how to comment your essay, it's awesome and superb. I am so jealous, I hope I can write the essays like you.
BTW, the boxing game Chinese female athlete Ren cancan was lose, I am so upset. But Katie deserve the champion.