英语听力：探索发现 科学新发现：我们的大气层-11

 The planet also began releasing oxygen, thanks to an ancient adoption¹ of photosynthesis². A very ancestral primitive³ plant cell either engulfed⁴ or tried to digest or surrounded a cyanobaterium and instead of digesting it, it actually became an organ within the planet. So every bit of the oxygen, even if it’s coming from a plant that you use in your yard, is coming from an ancestor of a cyanobateria resident inside the plant. 

 

With the rise of oxygen, the air’s unique blend of gases was complete. The air we breathe has changed planet Earth, moulding its terrain⁵ and habitats. But as we continue our upward journey, we run into another vital substance, water. 

 

The turbulent movement of our atmosphere carries water vapour around the globe. Powerful winds and violent storms smash our buildings and drown out fields. But without them the land would be bone dry.

1 adoption   

n.采用，采纳，通过；收养

参考例句：

• An adoption agency had sent the boys to two different families.一个收养机构把他们送给两个不同的家庭。
• The adoption of this policy would relieve them of a tremendous burden.采取这一政策会给他们解除一个巨大的负担。

2 photosynthesis   

n.光合作用

参考例句：

• In apple trees photosynthesis occurs almost exclusively in the leaves.苹果树的光合作用几乎只发生在叶内。
• Chloroplasts are the structures in which photosynthesis happens.叶绿体就是光合作用发生的地方。

3 primitive   

adj.原始的；简单的；n.原(始)人，原始事物

参考例句：

• It is a primitive instinct to flee a place of danger.逃离危险的地方是一种原始本能。
• His book describes the march of the civilization of a primitive society.他的著作描述了一个原始社会的开化过程。

4 engulfed   

v.吞没，包住( engulf的过去式和过去分词 )

参考例句：

• He was engulfed by a crowd of reporters. 他被一群记者团团围住。
• The little boat was engulfed by the waves. 小船被波浪吞没了。 来自《简明英汉词典》

5 terrain   

n.地面，地形，地图

参考例句：

• He had made a detailed study of the terrain.他对地形作了缜密的研究。
• He knows the terrain of this locality like the back of his hand.他对这一带的地形了如指掌。