1. hard and fast的翻译

1. 不能改变的：free and easy 随和 | hard and fast 不能改变的 | open and above board 光明磊落

2. 严格;严密：Happiness lies first of all in health. 幸福首要是健康 | hard and fast 严格;严密 | Harm set; harm get. 害人反害己

3. (规则等)严格的：learn sth the hard way经过艰难困苦而学到 | hard and fast (规则等)严格的 | hardwaren.金属日用器皿,计算机硬件

4. 不可违逆的：hard 硬的 | hard-and-fast 不可违逆的 | hard-bitten 不易对付的

1. （规则、信息等）固定不变的，明确的
    If you say that there are no hard and fast rules, or that there is no hard and fast information about something, you are indicating that there are no fixed or definite rules or facts.

    e.g. There are no hard and fast rules, but rather traditional guidelines as to who pays for what...
           关于谁来支付什么费用并没有明确的规定，只是遵循传统的准则罢了。
    e.g. At the moment there''s no hard and fast timetable.
           目前还没有明确的时间表。