We should help each other maintain the environment, do not throw down the River, and anything that can be recycled again, we should be reused repeatedly to conserve natural resources.
We should help save the environment as a dumping garbage into the river, and anything that can be reused again, I'd be reused repeatedly. In order to save resources
We should help to preserve the environment, such as no garbage into the river, and nothing can bring back the ใช้ได้อีก we should take. To save natural resources.