听力原文

However, the situation is improving . Anti-poaching laws are now actively enforced so every summer, female chiru can head to the birthing grounds in relative safety.
但是情况正在逐步好转，反偷猎法已经生效，所以每年夏天，母藏羚羊可以相对安全地带领羊群到繁衍的地方。
Out on the plateau, new-born chiru are vulnerable to predators, so the mothers must try to hide and protect them.
在高原上，新生的藏羚羊容易受到食肉动物的攻击，所以母藏羚羊必须把他们藏起来保护它们。
The most recent problem faced by the chiru is the new Tibet-Qinghai railway, which cuts right through their traditional migration routes.
藏羚羊最近遇到的最大问题就是青藏铁路的修建正好阻断了它们传统的迁徙路线。
It's too early to see its effect on the wildlife, but the engineers have made efforts to incorporate underpasses where wildlife can cross the line in safety.
评论它对野生动物的影响还为时过早，但工程师们已经设计了高架桥来让野生动物能安全地穿过铁路。
As the modern world increasingly impacts on Tibet, its traditions could be in danger of being eroded.
由于现代世界对西藏与日俱增的影响，西藏的传统文化正面临影响。
Running nearly 2,000 kilometres through some of the highest terrain on Earth, the railway is an astonishing technical feat.
青藏铁路蜿蜒2000多公里，经过世界上最高的地带，它的建造技术是震惊世界的壮举。

重点讲解

重点讲解：
1. head to
前往；引至，通到；
eg. Disobeying the law can head to trouble.
不守法可能会引起麻烦。
eg. In the summer many residents head to cape cod and newport beach, rhode island.
一到夏天，许多居民就前往科德角、纽波特海滩和罗德岛。
2. be vulnerable to
易受伤害的；易受影响的；
eg. But in today's economy, educated, white-collar workers also are vulnerable to downsizing.
但是,在今天的经济中，受过教育的白领工人也同样容易受到裁员的攻击。
eg. A system without anti - virus software will be vulnerable to a hacker attack.
没有防毒软件的系统很容易被黑客攻击。
3. in dange of
处于…危险之中；
eg. The plant is now in danger of extinction.
这种植物现在有绝种的危险。
eg. He was in danger of losing his life.
他有失去生命的危险。