英语资讯
News

新编六级听力练习 第238期

Source: 恒星英语学习网    2020-04-16  我要投稿   论坛   Favorite  

Test 3
If the population of the Earth goes on increasing at its present rate, there will (36) ______ not be enough resources left to (37) ______ life on the planet. By the middle of the 21st century, if present (38) ______ continue, we will have used up all the oil that drives our cars, for example. Even if scientists develop new ways of (39) ______ the human race, the (40) ______ conditions on Earth will make it necessary for us to look for open space somewhere else.
An American scientist, Professor Carl Sagan, believes that before the earth's resources are completely (41) ______ , it will be possible to change the (42) ______ atmosphere of Venus and so create a new world almost as large as Earth itself. The difficulty is that Venus is much hotter than the Earth and there is only a (43) ______ amount of water there.
(44) ____________________________________________________________________ . As soon as this has been done, the algae will be placed in small rockets. (45) _____________________________________________________ . In a fairly short time, the algae will break down the carbon dioxide into oxygen and carbon.
When the algae have done their work, the atmosphere will become cooler but before man can set foot on Venus, it will be necessary for the oxygen to produce rain. (46) _____________________________________________________ .


将本页收藏到:
上一篇:新编六级听力练习 第237期
下一篇:新编六级听力练习 第239期

最新更新
论坛精彩内容
网站地图 - 学习交流 - 恒星英语论坛 - 关于我们 - 广告服务 - 帮助中心 - 联系我们
Copyright ©2006-2007 www.Hxen.com All Rights Reserved