计算理论为理解什么可以计算、什么不能计算提供了基础。
Sustainability isn't an option anymore—it's a necessity for survival.
"To travel is to discover that everyone is wrong about other countries."
及时采撷你的花蕾,旧时光一去不回,今天尚在微笑的花朵,明日便在风中枯萎。