英语听力：自然百科 澳大利亚大堡礁 Great Barrier Reef—10

 But the wonky holes will never be completely covered up, because coral can’t grow in freshwater. They’ll remain an indelible reminder¹ of the reef's past lives. But the origins of the reef lie even further back in time. And to understand them means cracking one of the Southern Hemisphere’s greatest mysteries.

 

It takes a unique set of circumstances to build something the size of the Great Barrier Reef, the most important of which is its perfect location. 

 

This entire reef sits in the tropics. And that means warm water and strong sunlight all year round. Without them, it simply could not grow to this colossal² size. So how did the Great Barrier Reef end up here perfectly³ located? Has it always been here? The geological evidence says no. 

 

Incredibly, it seems Australia started life about as far south as you can get, as part of Antarctica, far too cold and far too dark for this epic⁴ reef. But the evidence of this incredible transformation⁵ isn't in the sea. It's found inland. Something so big, it transformed this place from a cold, dark world to a warm, tropical paradise.

 

The answer is locked up in a series of mountains that stretch up Australia's eastern coast, like rocky backbone⁶, called the Great Dividing Range. Geological super sleuth Kurt Knesel is on the hunt for the right mountain, one that holds the answers. But this mountain range is 2000 miles long, so he’s working with a paraglider Will Gadd to cover more ground. Kurt is looking for this spectacular peak. It is called Mount Warning, and it has a violent past.

1 reminder   

n.提醒物，纪念品；暗示，提示

参考例句：

• I have had another reminder from the library.我又收到图书馆的催还单。
• It always took a final reminder to get her to pay her share of the rent.总是得发给她一份最后催缴通知，她才付应该交的房租。

2 colossal   

adj.异常的，庞大的

参考例句：

• There has been a colossal waste of public money.一直存在巨大的公款浪费。
• Some of the tall buildings in that city are colossal.那座城市里的一些高层建筑很庞大。

3 perfectly   

adv.完美地，无可非议地，彻底地

参考例句：

• The witnesses were each perfectly certain of what they said.证人们个个对自己所说的话十分肯定。
• Everything that we're doing is all perfectly above board.我们做的每件事情都是光明正大的。

4 epic   

n.史诗，叙事诗；adj.史诗般的，壮丽的

参考例句：

• I gave up my epic and wrote this little tale instead.我放弃了写叙事诗，而写了这个小故事。
• They held a banquet of epic proportions.他们举行了盛大的宴会。

5 transformation   

n.变化；改造；转变

参考例句：

• Going to college brought about a dramatic transformation in her outlook.上大学使她的观念发生了巨大的变化。
• He was struggling to make the transformation from single man to responsible husband.他正在努力使自己由单身汉变为可靠的丈夫。

6 backbone   

n.脊骨，脊柱，骨干；刚毅，骨气

参考例句：

• The Chinese people have backbone.中国人民有骨气。
• The backbone is an articulate structure.脊椎骨是一种关节相连的结构。