参考答案： Human Activity and the Earth
That human activity has an effect on our planet is beyond doubt. While some of man’s accomplishments have made the Earth a better place for people to live in, they have not come without cost. Overall, it seems that human activity harms the Earth more than it benefits it.
For example, the transportation systems that benefit mankind also pollute the air and use up valuable energy resources. Additionally, accomplishments such as the supply of potable water are only responses to problems that mankind created in the past. In the first place, it was man that made the water unhealthy to drink.
All in all, the damage that human activity causes will eventually have a negative effect on people. They will suffer the effects of pollution and gradually diminishing natural resources.