英语听力：自然百科 北极熊 冰上间谍 Spy_Bear—7

 She leaves little behind. 

 

Males are still on the lookout¹ for females. For her cub²'s safety, she heads back to the hills. But as spring continues, lengthening³ days bring sudden and dramatic change. The highest tides of the year combine with the rising temperatures to trigger a vast of breakup of the ice that surrounds the islands.  In just one night, it can crack apart and drift 20 miles or more. Svalbard is a series of islands once more. 

 

The mother and single cub are still on the snowy hills, but signs of change are all around. 

 

At the shoreline, things are not as expected. The sea ice has drifted northwards and with it the bears' food supply. It's a huge swim for an adult bear. For the cub, it's out of the question. Their ship has sailed and left them behind. They are marooned⁴ on the island for the summer. 

 

The two-cub family managed to board the sea ice before it drifted too far.

1 lookout   

n.注意，前途，瞭望台

参考例句：

• You can see everything around from the lookout.从了望台上你可以看清周围的一切。
• It's a bad lookout for the company if interest rates don't come down.如果利率降不下来，公司的前景可就不妙了。

2 cub   

n.幼兽，年轻无经验的人

参考例句：

• The lion cub's mother was hunting for what she needs. 这只幼师的母亲正在捕猎。
• The cub licked the milk from its mother's breast. 这头幼兽吸吮着它妈妈的奶水。

3 lengthening   

（时间或空间）延长，伸长( lengthen的现在分词 )； 加长

参考例句：

• The evening shadows were lengthening. 残阳下的影子越拉越长。
• The shadows are lengthening for me. 我的影子越来越长了。 来自演讲部分

4 marooned   

adj.被围困的；孤立无援的；无法脱身的

参考例句：

• During the storm we were marooned in a cabin miles from town. 在风暴中我们被围困在离城数英里的小屋内。 来自《现代英汉综合大词典》
• Five couples were marooned in their caravans when the River Avon broke its banks. 埃文河决堤的时候，有5对夫妇被困在了他们的房车里。 来自辞典例句