PS There is no minimum or maximum length for the personal statement. Brevity is preferred. The statement serves as both a writing sample and opportunity for you to explain, why you are applying, what makes you a good fit, and anything that may be unclear elsewhere on your application. CV Resumé or Curriculum Vitae Fee $85 non-refundable application fee RL Three recommendation letters. A letter that addresses recollections of favorable personal interactions in a classroom or a laboratory setting is very valuable. Letters from professors in the student's department who have direct experience with the student and can clearly compare him/her to others in this class or prior classes are effective.（详情见http://gradengineering.columbia.edu/application-materials） Transcript The transcript copy you upload onto your online application must be an official copy, which is typically obtained from your college or university Registrar's office or the office that issues official transcripts to students. Uploading anything other than a copy of your official transcript may cause delay in the review of your application.