plankton produced so much oxygen that it transformed our planet. 浮游生物产生了大量氧气 使我们的星球发生了巨大改变
Our changing planet has created so many challenges for life. 我们不断变化的星球 为生命制♥造♥了诸多挑战
until eventually, one will be so different to its predecessors 直到最终与其祖先截然不同
Never has learning been given to so many human beings. 从来没有过这么多人可以接受教育
It is so cold that the ground is constantly frozen. 由于天气寒冷形成了冻土层
Hasn't been so high for several hundred thousand years. 二氧化碳浓度从来没有如此之高