Plagiarism Guide

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What is Plagiarism

You probably understand plagiarism as stealing someone else's words as your own. In fact, there are many different kinds of plagiarism. The top 4 types are:


This is exactly what it sounds like! If you take a sentence or a unique turn of phrase and pass it off as your own, this is stealing. It is stealing even if you paraphrase the authors words and don't cite your source.


Mary is writing a paper and wants to include ideas expressed by an author in a very difficult to read paper. After trying to write the ideas in her own words, Mary decides that the author wrote it better than she ever could and cuts and pastes the text into her word document. Unfortunately, she doesn't give the proper citation or put the text in quotes and her professor easily spots the foreign text and fails her for plagiarism.


When you quote another author in your own work, always be sure to quote exactly what was said. Never change or misrepresent another's words to make your own argument stronger.


Tom is writing a persuasive essay about a controversial topic and wants to make his argument even more convincing. Unfortunately he can't find exactly the right quote but he does find one where the author uses language like "perhaps" and "suggests". By modifying those words to make the author's sentence stronger, Tom feels pleased that his paper makes a convincing argument. Unfortunately, the professor is familiar with the author's research and realizes that Tom changed the author's results.

Insufficient Paraphrasing

Taking an author's words and changing them slightly, without quoting the actual text is plagiarism. If you can't say at least two-thirds of the passage in your own words, put the author's text in quotes and reference the source. Instructors can easily tell when this happens because everyone has their own style of writing and seeing styles change throughout a document is a red flag that plagiarism has occurred.


Sandra wants to use the quote:

"This result calls into question the assumption that organisms—even if present—necessarily played an essential role in determining stromatolite morphology during times when precipitation at the sea floor was common, such as the earlier Precambrian." (Grotzinger & Rothman, Nature, 1997).

Instead of putting the exact authors' words in quotes, Sandra writes:

Grotzinger and Rothman's (1997) results call into question the assumption that organisms play an essential role in determining stromatolite morphology during the earlier Precambrian.

While grading, the instructor notices that the tone of Sandra's writing changed and and checks the cited paper. Even though Sandra gave cited the authors, she is still guilty of plagiarism because the majority of her sentence was stolen directly from the article.

Duplicating Publication

You can not reuse/recycle your own paper/words for use in another assignment without explicit permission from the instructor. This is plagiarism and it is possible to plagiarize yourself if you don't give credit to your own work.


Leslie was just assigned a paper on black holes for her Galactic Astronomy class. She is swamped with homework right now and remembered that she wrote another paper on black holes the previous year in her Introduction to Astronomy course. That paper was even longer that what is required for this assignment so she took out a few paragraphs and resubmitted it for credit. The professor was surprised at the basic level of Leslie's writing and called her in for an appointment to discuss the paper. When she admitted that it was a paper she had previously wrote, the professor told her that this was considered self-plagiarism and that papers that had been previously turned in for credit were not allowed to be resubmitted for another grade. The professor added that in the future Leslie should ask for permission first and that the professor would be speaking to Leslie's academic advisor about the situation.