Professor Roark says corals are important because they support many other forms of sea life.

VOA: special.2009.05.12

that human life is in some ways essentially different than other forms of life.

那就是人的生命从许多方面来说和其他形式的生命有本质的不同。

需要动物实验吗？ - SpeakingMax英语口语达人