如何区分hold the belief和hold a belief,

the 和 a 的区别就是后述的那个 belief 是“指定”（即众人所知）和 “非指定”.
hold the belief 表达一个指定、已知的观念
hold a belief 意味着该观念也许还不是公认的
我们最常看到的是 hold the belief 的形式,（而且后面通常有个 of 引导的名词短语 或 that 引导的从句)
例句：
Chinese society have always held the belief that children should honour and respect their parents.
Most people hold the belief of looking out for number one.It is only human nature.
Aheists hold the belief that there is no God.Is it logical to hold a belief without any evidence?这个句子用 a （虽然也可以用 the ）是因为all things will get better if they work hard的 belief 是第一次这里提到（即不是前述），belief 这里提到后，接下去就可以用 the belief 了。比如It is more difficult for graduates to make a livng in the present societybut they must hold (a) belief that all things will get better if they work hard.This will keep them going, even if (the) belief later turns out to be wrong.