你好,
only know... reduce it 也许可以改为:
What we can do is to adopt some advisable methods to diminish the pollution.
building...system 也许可以改为:
building a system to collect plastic bags
What's more...plastic bag 也许可以改为
Furthermore (additionally), using cloth bags is a more sustainable way to substitute the use of plastic bags.
The problem...actions 也许可以改为:
The problem can be solved if we take effective actions.
And...better也许可以改为:
(Eventually/to sum up) The less white pollution, the better our environment.
不知道这样好不好,只是个人观点而已。谢谢🆗