请教一下推荐人的问题

一般申请要写两封推荐信，一封我是找副总裁写，是没有什么问题了。但是另外一封，我本来想找以前的系主任写，他也答应我了，但是我本科时候成绩不是很好，如果吹牛太厉害，怕系主任不同意，如果比较实际一些，那对我申请也没有什么好处。所以，我在想，是不是可以让我大学4年的同学，也是我室友，我们也一起做了很多有价值的社会实践，来帮我写这封推荐信。他现在在新加坡的淡马锡做投资经理。相比较而言，是我同学好？还是系主任好？（我的系主任是清华大学经济系的系主任）

请教一下大家，谢谢！

看看学校对于推荐人的要求吧，在申请说明里都有。

有的学校要两封都是工作相关的人写，有的要一封是工作的领导，一封是学校的教授。

还有学校一般不接受同学、朋友、亲属推荐。

那看来很危险啊，只能再做做系主任的工作了，听说不少人都是自己签名，然后给写推荐信的人打个招呼，就说用了他的名义就行了？

how many years have you worked? do you apply to mba? if so, suggest to use recommendations all from work. your dean can really say nothing about your professional strength or extracurricular involvement. if the school requires three letters of recommendation, you can use academic one. but if only two, better to find another one from work, i.e. direct supervisor, big boss, client, etc. as for your classmate, it is not a good idea to have him write the letter. his work experience or title, whatever impressive, has nothing to do with your application - you are not colleagues, neither do you have interaction in a professional environment, right? a parallel is: i personally know some big shot such as bill g, but do i take any credit if having him as my recommender? the answer is no because he can say less about what i did at work, my performance, my achievements, my weakness, etc.