请帮我的托福作文评分,再评论一下,说明有哪些地方需要改进?谢谢!

请帮我的托福作文评分,再评论一下,说明有哪些地方需要改进?谢谢!
题目：
In twenty years there will be fewer cars in use than there are today.

正文：
I totally believe that there won't be as many cars as there are today in use in the future.

The first season why I hold this opinion is that our society is starting to encourage green development. As we all know, human has polluted our environment greatly. We cut abundant trees, pouring contaminated water into the river or sea, burning too much fuel for transportation, etc. One of the terrible outcomes is commonly known---global warming. The problem is so serious that even several international meetings were held to deal with it. In fact, most scholars who has studied global warming believe that transportation tools, such as cars and trucks, are to be blame for releasing a large amount of carbon dioxide into the air. Therefore, more and more people appeal that we should use "green" transportation tools like bicycles.

Besides, people are starting to also prefer riding bicycles or even going to work on foot, if not living too far away their workplace, because they want to live a healthier life. As the competition in the society intensifies, we spent much more time sitting in front of our desks and working on the computer. Work occupies our time for doing exercise, making our body much more delicate than before. Consequently, since an increasing number of people have realized the problem, they have begun to make use the commuting time to exercise by riding bicycles and walking to the office.

In sum, I think the use of cars is now reaching its peak. Since people lay more emphasis on protecting the environment and keeping healthy, it is very likely that fewer cars will apear in the streat in twenty years. Instead, other environmentally friendly transportation tools like bicycles may turn out to be popular again.