1·It is one of the unwritten laws of business, a matter of simple percentages.
这句话是商业经营的不成文规则，就是简单的百分比问题。
2·Preserving that kind of social hierarchy is an unwritten assumption in deciding which solutions to the world's problems arrive on the table and which do not.
在解决世界即将面临的问题的时候，选择或者不选择哪种解决方案的不成文的前提是保持现有的这种社会等级制度。
3·It is because, given high levels of illiteracy, many Afghans and Pakistanis find it easier to understand unwritten customary law, in Pushtu called narkh.
原因在于，由于高文盲率，许多阿富汗人和巴基斯坦人发现更容易理解不成文的习惯法（customary law[font=宋体]），普什图语中称为“narkh[font=宋体]”。
4·Here's why: Valley culture has an unwritten rule that if you don't like a job, or if you think your company isn't going anywhere, you leave.
这就是为什么：硅谷文化有一个不成文的规矩，如果你不喜欢某个工作，或者你觉得公司没啥前途，你走人即可。
5·Luckily, I had a mentor who helped me figure out the unwritten rules.
幸运的是，我找到了一位导师，帮助我理解了那些不成文的游戏规则。