Paraphrased essays intended to hide the true author, papers written by another hand or wholesale copy and pastes which are then submitted as the student's own work is cheating, simple as that. AE has helped many students studying abroad who are wrestling with the inconsistancies and often tortuous grammar of the English language. However the documents you submit should be your own writing or cited and referenced in the proper manner. As it says throughout this site 'we love words' communication is our thing and long may we continue helping in our own small way the education and development of our clients.
Cartoon from http://www.ethicssage.com/business-ethics/