The clouds over the land now rose like mountains, and the coast was only a long green line with the gray blue hills behind it. The water was a dark blue now, so dark that it was almost purple.

数学家的工作永无止境；总有新的问题要问，新的谜题要解。

Innovation in the gas sector must balance immediate needs with long-term sustainability goals.

你没有被你的过去定义。你被你的过去所准备。