听力文本

Invertebrates dominate these upper reaches.
无脊椎动物统治着上游河段
The hellgrammite, its body flattened to reduce drag,
这是鱼蛉，其扁平的身体能减少水的冲击力
has bushy gills to extract oxygen from the current.
并依靠浓密的鳃从水中过滤氧气
Black fly larvae anchor themselves with a ring of hooks.
蚋的幼虫靠钩环固定自己
But if these become unstuck, they're still held by a silken safety line.
即使不小心松脱了，它们还有一根坚韧的“安全索”

There are advantages to life in the fast stream.
这些动物拥有在急流中生存的先天优势
Bamboo shrimps can just sit and sift out passing particles with their fan-like forearms.
拟匙指虾只需趴在河底，用它们的扇形前臂从流水中过滤出食物颗粒
Usually these mountain streams only provide enough food for small animals to survive,
通常，山涧提供的食物只能维持小型动物生存
but with the spring melt here in japan, monsters stir in their dens.
可是在日本，每当春雪消融之际，一种怪物便在巢窟中苏醒。

词汇解析

1.extract from 从...提取
We have several professional comedians in our club, and I've been amazed at just how much humor they're able to extract from our meetings.
我们俱乐部里有几个专业的喜剧演员，对他们从会议内容中提取幽默元素的能力，我总是感到很惊喜。

2.be advantages to 对...有好处
Mossberg then asked if there would be advantages to having two different carriers in the U.
Mossberg接着问在美国拥有两个运营商是否有好处。

3.sift out 筛选；过滤
You then sift out the pips, skins, stalks etc and further reduce the puree, before pouring it into well-oiled trays for drying.
滤出果核、果皮、茎干等，进一步提炼糊糊，然后倒入光滑的托盘里等待干燥。

视频及简介

淡水是我们最宝贵的资源，它决定了地球上生命的分布。同河流一起，从高高的山峰一路而降，直向大海，观看壮观的瀑布，在大峡谷里飞翔，在世界上最深的湖泊的冰雪下面探索野生的生命，见证动物行为的独特的、生动的一面：水獭和泽鳄将一决胜负。