The ozone layer was destroyed, resulting in global warming and greenhouse effect. The icebergs were melted and the sea evolved into deserts. The depletion of the ozone layer brought damages to the human immune system, cataracts and increased incidence of skin cancer. Therefore, human beings must be kind to the earth and nature. Development centering around speed and quantity or at the expense of the environment is not acceptable. We should emphasize the harmony between human and nature and recognize the role of the ozone layer.