如何给心仪的导师写邮件，实际上就是该如何跟导师套磁，是申请 PHD 和研究型 master 过程中的重要一环，卡耐基梅隆大学的教授 Scott E. Fahlman 从教授的角度告诉大家该如何更高效、更有针对性地套磁。
以下内容译自 Scott E. Fahlman在quora上的回答：
我曾经收到过很多很多的套磁信，所以今天我想来谈谈我对套磁信的看法。
首先，我非常不能接受群发套磁信。
无论什么情况，所有的教授都不希望收到的是一封垃圾邮件，一封随便发送给同一个学校十几位甚至几十位教授的套磁信就是一封垃圾邮件，这说明你根本就没有针对性或者没有诚意地想加入我们。
其次，有些套磁信不够具体，甚至连称呼都没有。
有的学生发来的套磁信中只有一个简单的开头 Dear Professor，连具体的学校和项目名称都没有，也完全没有提到我的科研内容，更没有提到自己的兴趣或能力是否和科研项目相关，或者只是在官网上简单地找了几个相关的关键词就说对这个方向很感兴趣，但是这完全看不出来你有用心了解过我的研究方向或内容啊，甚至有时候说的关键词还是错的，根本就不是我的研究方向！
通常收到这样的千篇一律不真诚的套磁信， 我都会直接删除了 ，或者发一个关于项目介绍的官网链接，但是，基本上就算你后来去查了这个链接，我也不会再考虑这个学生了。
所以，如果一个学生真的想加入到我的团队，在发邮件之前， 至少应该花点时间了解一下我到底在做些什么研究，细节越多越好，可以查相关的论文。 这不仅仅是对教授的一种尊重，更是对自己的负责，只有你真正了解了教授的研究方向，你才能知道这些东西是不是你感兴趣的。
如果上述前提确定好，那么我想我最关心的， 也是大部分教授最关心的就是你的科研背景是否和我的项目相匹配。
所以，在信中清晰地说明自己的科研背景、做过的项目、发表论文的情况、掌握的技术以及自己未来想从事的研究方向是整个套磁信中最重要的部分。同时，如果能结合自己和教授的情况，说明自己能够为项目提供的帮助也是很有必要的。尽管具体的匹配程度需要教授自己来判断，但是逻辑清晰、语言准确地推销出自己也能够让教授看到你的能力或者潜力，即使不是完美匹配，教授也会认真考虑。
基于以上，我认为一份好的套磁信应该 直截了当地介绍自己的基本情况，然后重点说明自己的科研背景和对项目的了解、匹配程度，可以适当询问教授项目的具体情况。如果教授对你感兴趣，自然会回答你的问题或者询问你更多细节问题。
另外，教授是否回信大多取决于以下几种情况：教授有多忙，你有多优秀，你的英语表达能力，你有多么想为这个教授工作。
并且，套磁信尽量早点开始， 这样你可以有更多时间跟教授联系，如果在申请旺季开始，每天我的邮箱里会收到茫茫多的套磁信，恐怕能不能看到你的邮件都是问题。
最后，套磁并不能保证录取。 哪怕我很喜欢你，但是如果我当时没有项目资金再多雇一个人，或者出现了更好的候选人，那我也没办法要你。但是，如果我真的很欣赏你，也许我可以推荐你到其他教授或者其他项目那里。
以下是原文，可能会让你更好地体会教授想表达的东西。
How o I write the first email to a professor that may accept me as his grauate stuent?
I get a lot of letters of this type. Let me tell you what NOT to o.
The first contact shoul not be a spam letter &nash; that is, a letter that you coul easily have sent to 1000 faculty members worlwie, an probably i. Why shoul I spen more time answering your letter or reaing your resume/CV than you spent writing the letter?
Often the letter is not even minimally customize. It is aresse to &lquo;Dear Professor&rquo; an oes not mention the project name or the university, even though you think my work is wonerful an esperately want to work with me. The letter gives no inication that the writer has spent even a few minutes looking at the online materials relate to my work. An then these har-working people, so passionate about my work, go on to say that they want to work with me on &lquo;algorithms, ata mining, software engineering, an computer vision&rquo; &nash; not areas that I currently work in.
Often I throw these notes in the trash immeiately, or respon with a canne message pointing to a web page with info about how to get into a CS grauate program at CMU an about the specific issues of joining my group. (In case you’re intereste, see Page on cmu.eu.)
But once you sen me that spam letter, there’s no point in then going online an fining out what I o. You’re alreay a loser.
So if you think that you really want to work with me as a grauate stuent, first take some time to fin out what kin of research I really o. Then, if you have no experience or preparation in this area, get some. Rea an think about my papers (an the essays on my blog), an some papers in relate areas. Think about what you might be able to a to this, an what it will take to get up to spee. Do your homework. Then write me a brief letter, making specific reference to all of that.
Then maybe we can talk, an maybe something will come of it.
&nash; Scott Fahlman
P.S. It occurs to me that there’s something else I shoul have sai: Yes, you shoul know what the professor works on, an shoul know enough about the fiel to know whether this work really interests you, before you bother a busy professor at all.
But, given that, the best kin of first-contact is a letter one saying, &lquo;I’m a stuent in my X year of Y university. I’m intereste in your work on X (be specific) an woul like to learn more about it. Can you suggest the best way to o that?&lquo; You may get a canne answer, but that’s just because we all get so many of these queries. Rea that stuff or play with the coe, think about it, an see if you are still really intereste. Maybe follow up, asking a specific question or two about the work, or try some little project base on the professor’s work.
Whether the faculty member chooses to carry on such a corresponence epens on several things: how busy the professor is at that moment, how goo you seem to be, whether there’s a communication problem, an whether you seem to be truly intereste in his or her work. Don’t keep talking about how intereste you are &nash; prove it! An try not to be too much of a loa.
I’ve ha a few corresponences of this type, an in a couple of cases it has le to my supporting the stuent for amission to one of our grauate programs. It’s best to start this early, so that by the time the iscussion gets aroun to grauate amissions, I have a very goo iea of whether I woul like you as a gra stuent. Even if I like you, this still might not happen &nash; it epens on whether I have an opening (an funing) for a new stuent that year an how goo the other caniates are &nash; but this is by far the best way to get starte. If I can’t take you on, at least you might learn something interesting, an maybe I can suggest other faculty or other programs that might be a goo fit for you.
