Professors should let students know that plagiarism is recognizable and is not tolerable, and should place a clear plagiarism statement in class syllabi. Professors should obtain a two-page, hand-written writing sample from each student on the first day of class. They will be able to compare this writing with any questionable latter writings.
Collecting the Clues
Watch for exceedingly well-written prose. If a paper on the topic of cell structure sounds as if it could be published in a textbook, it possibly was. Pay attention to complex sentence structure and sentences that contain multiple complex clauses or difficult juxtaposed wordings. Notice well-thought out sentence fragments. Seasoned journalists often use fragments to good effect. Students, on the other hand, rarely use them effectively. Are there oddly placed "personalized" ethos in the middle of mundane or superficial essays? Students who obtain papers from internet paper mills often add a sentence here or there to sculpt a generic essay to better fit the class. Finally, take note of odd grammatical errors and misspellings. Students will often attempt to "dumb down" a plagiarized paper. However, it is more than likely that these students do not know enough about grammar and phonemic structures to make "typical" mistakes. If an error strikes you as odd, look more closely to see if some paragraphs are better written than others.
Evidence is absolutely crucial when making an allegation a student of plagiarism. These are a few methods of searching out a student's paper.