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- earth rs gravity 地球引力
- Most of the earth rs surface is covered by water. 大部分的地球表面被水覆盖着。
- Earth quakes can result from stresses in the earth rs crust. 地壳内的应力可能引起地震。
- The sun appears to rise and set because of the earth rs rotation. 因为地球在自转，看上去就有了日出和日落。
- Lunar eclipse occurs when the earth rs shadow falls on the moon. 地球的影子落在月球上时，就发生月蚀。
- Children supporting their parents is nature rs law and earth rs way. 子女奉养父母是天经地义的。
- The force of gravity pulls things towards the earth's centre. 地心吸力把物体吸向地心。
- earth rs line of maximum atmospheric gradient 地球最大大气梯度线
- the loose mass of the earth rs crust 一层松散物质
- earth rs gravitational field model 地球重力场模型
- Our pilotless rocket enters the track of the earth. 我们把一个无人驾驶的火箭送入了地球的轨道里。
- reentry into the earth rs atmosphere 重入地球大气层
- The force of gravity makes things fall to earth. 地心引力使物体落向地面。
- The attraction of the moon for the earth causes the tides. 月球对地球的吸引力造成潮汐。
- The earth is only a speck in the universe. 地球在宇宙中只不过是一个小点罢了。
- How on earth do they manage to rob the bank? 他们到底怎么抢了银行的？
- A number of satellites are now circling the earth. 一些人造卫星现在正环绕地球飞行。
- The machine cast up a big heap of earth. 机器卷起了一大堆泥土。
- The red sun lights up the sky and the earth. 红太阳照亮了天空和大地。
- Who on earth is that female he's with? 跟他在一起的那个女人究竟是谁?
