听力原文

Elephants are the architects of the forest.
大象是森林的建筑师。
Bamboos and grasses are their favourite food, but saplings, tree leaves and twisted lianas are all taken, with little care.
竹子和草是大象最喜爱的食物，但是吃一些盘旋的藤蔓植物树苗以及树叶也无所谓。
As they move through the forest, the elephants open up clearings, bringing light to the forest floor.
大象开辟出了小块的林中空地为森林中的地面带来了阳光。
This has a major impact on their home. The richest forests are now known to be those which from time to time experience change.
这对它们的家园有着较大的影响。如今人们知晓，最繁密的森林，是那些不时经历变化的森林。

重点讲解

重点讲解：
1. open up
开辟；打通；
eg. As rescue workers opened up roads today, it became apparent that some small towns were totally devastated.
今天救援人员打通了道路后，人们发现一些小镇显然已被彻底摧毁。
eg. The sales manager wants to open up new markets in the Far East.
销售经理想在远东开辟新市场。
2. have an impact on sth.
对……产生影响；作用；
eg. Technology has had an irreversible impact on society.
技术已对社会产生不可逆转的影响。
eg. There's no question that the ads had a real impact on the public.
毫无疑问，这些广告对公众确实产生了影响。
3. from time to time
不时地；间或；偶尔；
eg. Her daughters visited him from time to time when he was ill.
他生病的时候她的女儿们时常去探望他。
eg. From time to time,she gave him an encouraging nod.
她不时对他点头鼓励。