听力原文

This might seem surprising given goats' reputation for eating anything green, but tea isn't as defenceless as it looks.
介于山羊会吃一切绿色的东西，这一点似乎有些奇怪。不过茶树并不像看上去那样毫无设防。
Tea leaves are loaded with bitter chemicals designed to repel browsing animals.
茶叶中存在刺激性的化学成分以驱走啃食的动物。
It works on the goats, who leave the tea untouched and instead eat up the weeds, fertilising the tea plants with their droppings.
这对山羊很有效，它们只是吃光茶树外的杂草，它们的粪便恰好茶树供给了养分。
The surprise is that we humans should find the same bitter chemical cocktail utterly irresistible.
令人惊讶的是，我们人类却为这种苦涩的化学混合物心醉神迷。

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重点讲解

重点讲解：
1. be loaded with
（特点）浓烈的，深厚的，丰富的；
eg. Traditionally, ice cream is made with heavy cream loaded with saturated fat.
传统而言，冰淇淋是由含有大量饱和脂肪的奶油制成的。
eg. The bough was loaded with fruit.
树枝上果实累累。
2. be designed to do sth.
计划；打算；意图；企图；
eg. The plan is designed to reduce some of the company's mountainous debt.
该计划旨在减少公司堆积如山的债务。
eg. Convenience stores have instituted new programs designed to increase sales of these types of products.
便利店已建立了新的计划，以增加销售这些类型的产品。
3. eat up
吃光；吃完；
eg. Some seed fell along the footpath, and the birds came and ate it up.
有些种子散落在小路上，鸟儿飞来把它们吃光了。
eg. He was so hungry that he ate up his meal at a stretch.
他太饥饿了，一口气就把饭吃光了。