北师大版高中英语模块7--Unit 22 Environmental 3

（单词翻译）

[00:01.94]Fresh water
[00:03.71]Rivers, lakes and wet-lands are sources
[00:06.23]of fresh water,not only for humans,
[00:08.50]but for wildlife too.
[00:10.35]Due to pollution and climate change,
[00:12.60]about 50% of the world's fresh water habitats
[00:15.09]have been destroyed in the last 100 years.
[00:19.15]And more than 3 billion people
[00:21.04]in poor countries
[00:22.31]do not have enough clean water.
[00:25.35]The WWF works hard to protect fresh-water
[00:28.53]environment from pollution and to help people
[00:31.87]in developing countries have access to safe,
[00:34.93]clean water.
[00:36.58]Nobody knows exactly how many species¹ of plants
[00:39.27]and animals there are on Earth.
[00:41.45]Scientists say that there would be as many as
[00:44.08]15 million different species.
[00:46.06]Sadly, many species have become extinct²
[00:48.92]and many are in danger of extinction³.
[00:51.63]But thanks to the hard work of organizations
[00:53.59]like the WWF,
[00:55.55]more and more have a chance to survive.
[00:57.23]