表建议之意时，advice 是一个不可数名词，不加an这样的冠词。
it was good advice or a good piece of advice.
它可以跟the，如 Unfortunately all the advice they gave me was wrong.
give advice用的时候，用the的例子没看到。
Financial advisors can be fined if they give bad advice to a client.
The programme aims to offer practical advice on healthy eating.
The website gives detailed advice about making bombs.
个人觉得还和语言使用习惯有关吧。