In college exams, we often need to send out some draft papers, which are often in different colors, because different colors represent an exam subject, so that we can clearly know which one this draft paper is after the exam, and it is convenient to destroy it in time. If you don't need it during the exam, you can also apply to the teacher.

At present, some universities have special workers to let students type Cao Yuan's draft paper during the exam. The name of the university is written on the draft paper, and the operation refers to different colors.