英语听力:自然百科 黄石公园的夏天 Yellowstone—10(在线收听

 As soon as she feels it is safe, she settles to suckle and reassure them. 

 
Bison can shrug off this sudden change in the weather; they are after all built to survive the Yellowstone winter.
 
But this tiny hummingbird is more vulnerable. Flowers damaged by snow will die, and the nectar the hummingbird needs goes with them. Hummingbirds must be resourceful to survive.
 
Bark wells dug by a sapsucker, a type of woodpecker, quickly fill with / sugar-rich sap as soon as the warm weather returns.
 
A little pilfering provides this hummingbird with the energy it needs until the new flower buds open. 
 
Summer moves quickly. By late June, the blizzards of a few weeks before seem/ a distant memory.
 
At last the summer is well enough established for this hummingbird to take the plunge and raise a brood.

 

  原文地址:http://www.tingroom.com/lesson/zrbaike/2012/273751.html