某个命题可以从某一组公理通过某一规则系统推导出来,这一事实本身并不使其为真。
If you fulfill your obligations everyday you don't need to worry about the future.
海洋生态平衡是我们共同的责任,破坏它就是破坏我们自己的未来。
The last temptation is the greatest treason: to do the right deed for the wrong reason.