Question

請將下面作文中劃線的句子改為被動語態，體會一下被動句的妙用。

　　①People generally believe that there is a good supply of fresh water．To our disappointment, the fact is just the opposite．

　　As we can see, the world population is growing rapidly day by day．②So we need enough fresh water to feed such a big population．What's more, with the development of industry, factories and vehicles produce poisonous gases or wastes, which consequently results in the pollution of water．③Though the water looks fresh, we can no longer use a good amount of it．Only quite limited fresh water resource is available to human beings．So it's high time for us human beings to take quick action to protect water resource．Stop pollution and save water, otherwise, we cannot survive on the earth．

Answer 1

答案：
解析：

①It is generally believed that there is a good supply of fresh water． 　　②So enough fresh water is needed to feed such a big population． 　　③Though the water looks fresh, a good amount of it can no longer be used．