How many species are we aware of? 我们已知多少物种呢

164. They make the humus,
     他们产生腐殖质
165. The fertile layer to which all life on land is linked.
     地球上所有的生命都与这富饶的土层有关
166. What do we know about life on earth?
     地球上的生命我们了解多少呢
167. How many species are we aware of?
     我们已知多少物种呢
168. A 10th of them? A hundredth perhaps?
     十分之一 百分之一
169. What do we know about the bonds that link them?
     他们之间的联♥系♥ 我们又知道多少呢
170. The earth is a miracle.
     地球是个奇迹

来自《家园 第一部分 Home Part1》第 167 行