March 22 is World Water Day. It started in 1993. It not only makes us think about the importance of water, but   also calls on（号召）us to___and protect water. Today, we're facing terrible water problems. Among them, the wastewater problem is rather ___, And the subject of World Water Day in 2017 is “wastewater”.

What is wastewater? It is used water.   Usually, wastewater comes from homes,___, hospital and so on. It is produced by different kinds of activities, including washing machines, taking showers and using kitchens. The rain also___wastewater when it is running down the street during a storm. No matter where it comes from, this kind of water is sure to have____harmful in it．

___must we treat（处理）wastewater? Wastewater has a big influence in our lives. It causes both illness for us and pollution for the environment. We must care for our environment and our own___.

How can we treat wastewater? Different kinds of wastewater need different ways of treatment. Wastewater___homes can be reused. Then there will be___wastewater. Also, factory wastewater has to be cleaned____it goes back to nature.

At 8, 844, 43 meters high, Mount Qomolangma is the tallest mountain on Earth. While it is famous for its beautiful views, parts of the mountain are facing a problem: rubbish. Every year, thousands of visitors throw away tons of rubbish, such as bottles and plastic bags.

According to the UN, over 140 tons of rubbish has been left on the mountain. To reduce rubbish, China is limiting(限制) the number of people who are allowed to climb up the north side of the mountain. Only 300 people will be allowed to climb it, and only during spring.

Local people cleaned the mountain last year, removing rubbish at a height of 5,200 meters. They collected about 8.4 metric tons(公吨) of rubbish。

This year, the local government plans to spend 4 million yuan on a new clean-up activity. The local government is also setting up stations to sort(分类), recycle and break down rubbish collected from the mountain. A group of artists will also try to turn the rubbish into art works. They will show these works of art to remind people not to leave rubbish when climbing the mountain.

61. 假设你叫李文，是阳光中学（Sunshine Middle School）的一名学生。今年暑期，你将代表你校赴瑞士参加“模拟联合国”会议并作发言，此次会议主题是A Greener World。你草拟了发言流程图，请根据下图写一篇英文发言稿。