``急求哪位英语大师帮我改出这篇文章里的语法错误~~~~~~全部改出再送50分!

``急求哪位英语大师帮我改出这篇文章里的语法错误~~~~~~全部改出再送50分!
Students have been using the same methods of cheating on exams for years. One tried-and-true technique is the casual glance. Pretending to stare thoughtfully out the window, peripheral vision will be used to look at another student’s paper. Another all-time favorite cheating method, the pencil or pen drop, requires a helper. Dropping a pen and then dive for it, the student whispers “Number seventeen” (or the number of some other question). Then, making a similar pen drop. The helper whispers the answer. The most elaborate cheatng system, though, is writing up cheat sheets. Tucked up a shirtsleeve, pages of textbook material are condensed into tiny scraps of paper, however, no matter how smooth a cheater’s style is, the time-tested methods are often ineffective. Having been a student at one time. The teacher is probably familiar to the same ones. Those students who think their “exam intelligence” is higher than their teachers often end up swallowing a bitter pill.