But even if there had been water, life doesn't start overnight. Even a simple microbe is the product of complex chemical systems that take millions of years to evolve. Had the water lasted long enough

发表于:2018-12-07 / 阅读(43) / 评论(0) 分类 火星生命

Unit 2 pizza In the pizza hot Id like to order a small pizza All right, do you want thin or thick crust? Oh, thin, I guess I am trying to loss weight You dont have to Thanks What about toppings?all pizzas come with cheese and tomato sauce, what els

发表于:2018-12-25 / 阅读(31) / 评论(0) 分类 移动英语

There is a special day to recognize the importance of the ozone layer. In 1995, the United Nations General Assembly decided September 16th is the International Day for the Preservation of the Ozone Layer. This is the date on which countries signed th

发表于:2018-12-29 / 阅读(105) / 评论(0) 分类 英语课程学习计划和讲义

Earth's Surfaces Are Always Moving 地球表面一直在运动 From VOA Learning English, this is Science in the News. Im Anna Matteo. And Im Christopher Cruise. Scientists who study the Earth tell us the continents and ocean floors are always moving

发表于:2019-01-12 / 阅读(36) / 评论(0) 分类 2014年VOA慢速英语(四)月

人类在地幔中找燃料 DIGGING in dirt and rock is big business. If you dig deep enough, with luck, you will strike oil or gas, which are used as our main sources of fuel and energy.Until now, we have only explored the Earth's outer

发表于:2019-02-03 / 阅读(26) / 评论(0) 分类 阅读空间

31. Although apparently rigid, bones exhibit a degree of elasticity that enables the skeleton to withstand considerable impact. 31. 骨头看起来是脆硬的,但它也有一定的弹性,使得骨骼

发表于:2019-03-13 / 阅读(198) / 评论(0) 分类 实用英语