个人经验，其实什么也不用买，纯属是浪费钱，出去了以后你连课本都读不完，再买书纯属是负担（还要搬家，除尘blahblahblah)。

你要实在无聊就看看剧，思考一下怎么和同学get along well。To be honest，我的阅读完全是出国后啃课本提升的，记的单词和material都很深刻，因为自己根据lecture的内容进行的二次的积极的学习，和盲目看书有很大区别的。What I try to say is that it would be a waste of time to read some useless books that have nothing to do with the major you are in. If you really want to be proactive, I would suggest you to log into your school's website and see if there is any required textbook that you can actually buy in China (fake version or pdf, of course). If so, you can also try to search if there is any syllabus that is available online (posted by former students who took the same course with you or shared the instructor with you) and then you can read the textbook according to the syllabus and I believe it would be super efficient.Take-Home Message: Studying abroad is not about studying a foreign language but using a foreign language to study their advanced technology, culture and etc. 千万不要为了提升阅读而阅读，而是为了提升你要学的specific的knowledge的能力而阅读。