1·We knew we were close to the roost when we slipped on the guano.
在鸟粪上滑了一跤！我们知道已经离鸟窝很近了。
2·The cave floor is covered in guano.
洞穴地底覆盖了满满的鸟粪。
3·It's used as a valuable source of fertiliser. A clue to the source of the guano can be heard above the noise of the river.
这是一种宝贵的天然肥料。鸟粪的源头能听到河水上空的鸟鸣。噪音因为山洞而被放大。
4·South America was famous for its guano and while there Humboldt did not forget to study why it was such a good fertilizer.
南美洲以鸟粪闻名，洪堡在那儿并没有忘去研究它为什么是这么好的肥料的原因。
5·People have been visiting this cave for generations. The cave floor is covered in guano, so plentiful that ten minutes' work can fill these farmers' baskets.
数代的人持续受到洞穴的恩泽，洞穴地底覆盖了满满鸟粪。仅仅十分钟时间就能让农人满载而归。