The following is an excerpt from the MLA Handbook for Writers of Research Papers, 5th Edition by Joseph Gibaldi, pp 30-34. Published in New York by the Modern Language Association of America, 1999. (See bottom of page for proper citation).

    Plagiarism in student writing is often unintentional, as when an elementary school pupil, assigned to do a report on a certain topic, goes home and copies down, word for word, everything on the subject in an encyclopedia. Unfortunately, some students continue to use such "research methods" in high school and even in college without realizing that these practices constitute plagiarism. At all times during research and writing, guard against the possibility of inadvertent plagiarism by keeping careful notes that distinguish between your own musings and thoughts and the material you gather from others. Forms of plagiarism include the failure to give appropriate acknowledgment when repeating another's wording or particularly apt phrase, when paraphrasing another's argument, or when presenting another's line of thinking.

    You may certainly use other persons' words and thoughts in your research paper, but the borrowed material must not seem your creation. Suppose, for example, that you want to use the material in the following passage, which appears on page 625 of an essay by Wendy Martin in the book Columbia Literary History of the United States.

Some of Dickinson's most powerful poems express her firmly held conviction that life cannot be fully comprehended without an understanding of death.

 If you write the following sentence without any documentation, you have committed plagiarism:

Emily Dickinson strongly believed that we cannot understand life fully unless we also comprehend death.

 But you may present the material if you cite your source.

As Wendy Martin has suggested, Emily Dickinson strongly believed that we cannot understand life fully unless we also comprehend death (625).

 The source is indicated, in accordance with MLA style, by the name of the author and by a page reference in parentheses. The name refers the reader to the corresponding entry in the works-cited list, which appears at the end of the paper.

     Martin, Wendy. "Emily Dickinson." Columbia
          Literary History of the United States.
          Emory Elliott, gen. ed. New York:
          Columbia UP, 1988. 609-26.    

Two more examples follow:

ORIGINAL SOURCE

Everyone uses the word language and everybody these days talks about culture [...]. "Languaculture" is a reminder, I hope, of the necessary connection between its two parts [...]. (Michael Agar, Language Shock: Understanding the Culture of Conversation [New York: Morrow, 1994] 60)

PLAGIARISM

At the intersection of language and culture lies a concept that we might call "languaculture."

ORIGINAL SOURCE

Humanity faces a quantum leap forward. It faces the deepest social upheaval and creative restructuring of all time. Without clearly recognizing it, we are engaged in building a remarkable civilization from the ground up. This is the meaning of the Third Wave.

Until Now the human race has undergone two great waves of change, each one largely obliterating earlier cultures or civilizations and replacing them with ways of life inconceivable to those who came before. The First Wave of change - the agricultural revolution - took thousands of years to play itself out. The Second Wave - the rise of industrial civilization - took a mere hundred years. Today history is even more accelerative, and it is likely that the Third Wave will sweep across history and complete itself in a few decades. (Alvin Toffler, The Third Wave [1980; New York: Bantam, 1981] 10)

PLAGIARISM

There have been two revolutionary periods of change in history: the agricultural revolution and the industrial revolution. The agricultural revolution determined the course of history for thousands of years; the industrial civilization lasted about a century. We are now on the threshold of a new period of revolutionary change, but this one may last for only a few decades.

 In the first example, the student borrowed a specific term ("languaculture") without acknowledgment; in the second example, the student presented another's line of thinking without giving credit. The students could have avoided the charge of plagiarism by rewording slightly and inserting appropriate parenthetical documentation.

At the intersection of language and culture lies a concept that Michael Agar has called "languaculture" (60).

According to Alvin Toffler, there have been two revolutionary periods of change in history: the agricultural revolution and the industrial revolution. The agricultural revolution determined the course of history for thousands of years; the industrial civilization lasted about a century. We are now on the threshold of a new period of revolutionary change, but this one may last for only a few decades (10).

 In each revision, the author's name refers the reader to the full description of the work in the works-cited list at the end of the paper, and the parenthetical documentation identifies the location of the borrowed material in the work.

     Agar, Michael. Language Shock: Understanding the
        Culture of Conversation. New York: Morrow.
        1994.
   Toffler, Alvin. The Third Wave. 1980. New York:
        Bantam. 1981.

    In writing your research paper, then, you should document everything that you borrow - not only direct quotations and paraphrases but also information and ideas. Of course, common sense as well as ethics should determine what you document. For example, you rarely need to give sources for familiar proverbs ("You can't judge a book by its cover"), well-known quotations ("We shall overcome"), or common knowledge ("George Washington was the first president of the United States"). But you must indicate the source of any appropriated material that the readers might otherwise mistake for your own. If you have any doubt about whether or not you are committing plagiarism, cite your source or sources.

    Two issues related to plagiarism do not deal with outside sources. The first occurs when a student submits in a course a paper done for a previous course. Although obviously not the same as stealing someone else's ideas, this practice nonetheless qualifies as a kind of self-plagiarism and constitutes another form of cheating. If you want to rework a paper that you prepared for another course, ask your current instructor for permission to do so.

    The other issue concerns collaborative work, such as a group project you carry out with other students. Joint participation in research and writing is common and, in fact, encouraged in many courses and in many professions, and it does not constitute plagiarism provided that credit is given for all contributions. One way to give credit, if roles were clearly demarcated or were unequal, is to state exactly who did what. Another way, especially if roles and contributions were merged and truly shared, is to acknowledge all concerned equally. Ask your instructor for advice if you are not certain how to acknowledge collaboration.

    A final related issue concerns copyright infringement. Because of the omnipresence of the Internet and the ease with which it is possible to download and duplicate Internet publications, many people think online materials are free to be reproduced and distributed at will. The truth is that most materials on the Internet, like most printed works, are protected by copyright law. Read carefully any special instructions or restriction specified in the document or at the site. Whereas summaries, paraphrases, and brief quotations in research papers are normally permissible with appropriate acknowledgment, reproducing and distributing an entire copyrighted document or significant portions of it without obtaining permission from the author or publisher to do so is an infringement of copyright law and a legal offense, even if the violator acknowledges the source. For a detailed discussion of copyright and other legal issues related to publishing, see chapter 2 of the MLA Style Manual and Guide to Scholarly Publishing (New York: MLA, 1998).