Writers sometimes plagiarize ideas from outside sources without realizing that they are doing so.  Put simply, you plagiarize if you present other writer's words and ideas as your own.  You do not plagiarize if you "provide citations for all direct quotations and paraphrases, for borrowed ideas, and for facts that do not belong to general knowledge" (Crews and VanSant, 407). 

General advice for using sources: 

The best way to avoid plagiarism is to keep control of your argument.  You should include ideas from other sources only when those ideas add weight to your argument.  Keep the following suggestions in mind when you are using material from other sources: 

* Select carefully. Quotations should give weight to your argument. In general, do not select quotations which only repeat points you have already made. 

* Be sure to integrate all ideas from other sources into your own discussion. Introduce direct quotations with your own words. After quoting, explain the significance of quotations.

* Avoid quoting more than is needed. Most of the time, brief quotations suffice. 

* Use direct quotations only when the author's wording is necessary or particularly effective. Some disciplines discourage direct quotations. Check with your professor. 

* If you are using material cited by an author and you do not have the original source, introduce the quotation with a phrase such as "as is quoted in...." 

* End citation alone is not sufficient for direct quotations; place all direct quotations within quotation marks. Be sure to copy quotations exactly as they appear. 

* To avoid any unintentional failure to cite sources, include all citation information on notecards and in your first draft. 

At all times, stay in control of your argument and let your own voice speak for you. 

A common pitfall: the notetaking stage 

Plagiarism often starts with the notetaking stage of the research process.  If possible, have a clear question in mind before heading off to the library so you will not waste time taking extraneous notes.  When taking notes, be sure to distinguish between paraphrases and direct quotations.  When you are copying a direct quotation, be extremely precise.  Note all the information you will need for the citation and copy the quotation exactly as it appears.  Some writers use only direct quotations when notetaking so there can be no confusion as to whether a note is a paraphrase or a direct quotation.  Other writers color-code notes: one color for paraphrases, another for quotations.  To ensure that you are not copying wording or sentence structure when paraphrasing, you might find it helpful to put the source material aside.  In summary, be consistent and conscious of whatever notetaking method you decide to use.

Examples: 

Sometimes writers do not recognize when their use of other writers' ideas constitutes plagiarism.  Versions of the following source can help you see the difference between acceptable paraphrasing and plagiarism (taken from The Bedford Handbook for Writers, 508).

Original source #1 

If the existence of a signing ape was unsettling for linguists, it was also startling news for animal behaviorists (Davis 26).

Version A 

The existence of a signing ape unsettled linguists and startled animal behaviorists  (Davis, 26).

Comment:

Plagiarism.  Even though the writer has cited the source, the writer has not used  quotation marks around the direct quotation "the existence of a signing ape."  In  addition, the phrase "unsettled linguists and startled animal behaviorists" closely  resembles the wording of the source.

Version B 

If the presence of a sign-language-using chimp was disturbing for scientists  studying language, it was also surprising to scientists studying animal behavior  (Davis, 26).

Comment: 

Still plagiarism.  Even though the writer has substituted synonyms and cited the  source, the writer is plagiarizing because the source's sentence structure is  unchanged.

Version C 

According to Flora Davis, linguists and animal behaviorists were unprepared for  the news that a chimp could communicate with its trainers through sign language  (Davis, 26).

Comment 

No plagiarism. This is an appropriate paraphrase of the original sentence. 

Original Source #2 

The joker in the European pack was Italy.  For a time, hopes were entertained of her as a force against Germany, but these disappeared under Mussolini.  In 1935 Italy made a belated attempt to participate in the scramble for Africa by invading Ethiopia.  It was clearly a breach of the covenant of the League of Nations for one of its members to attack another.  France and Great Britain, the Mediterranean powers, and the African powers were bound to take the lead against Italy at the league.  But they did so feebly and half-heartedly because they did not want to alienate a possible ally against Germany.  The result was the worst possible: the league failed to check aggression, Ethiopia lost her independence, and Italy was alienated after all ( J. M. Roberts, History of the World.  New York: Knopf, 1976, p. 845).

Version A 

Italy, one might say, was the joker in the European deck.  When she invaded  Ethiopia, it was clearly a breach of the covenant of the League of Nations, yet the  efforts of England and France to take the lead against her were feeble and half- hearted.  It appears that those great powers had no wish to alienate a possible ally  against Hitler's rearmed Germany.

Comment: 

Plagiarism.  The writer has taken entire phrases from the source, and there is no  citation.  The writer's interweaving of his or her own language does not mean that  the writer is innocent of plagiarism.

Version B 

Italy was the joker in the European deck.  Under Mussolini in 1935, she made a  belated attempt to participate in the scramble for Africa by invading Ethiopia.  As  J.M. Roberts points out, this violated the covenant of the League of Nations  (Roberts, 845).  But France and Britain, not wanting to alienate a possible ally  against Germany, put up only feeble and half-hearted opposition to the Ethiopian  adventure.  The outcome, as Roberts observes, was "the worst possible: the league  failed to check aggression, Ethiopia lost her independence, and Italy was alienated  after all" (Roberts, 845).

Comment: 

Still plagiarism.  Even though the writer has used two correct citations from the  source, he or she has not cited other phrases.

Version C: 

Much has been written about German rearmament and militarism in the period  1933-39.  But Germany's dominance in Europe was by no means a foregone  conclusion.  The fact is that the balance of power might have been tipped against  Hitler if one or two things had turned out differently.  Take Italy's gravitation  toward an alliance with Germany, for example.  That alliance seemed so very far  from inevitable that Britain and France actually muted their criticism of the  Ethiopian invasion in the hope of remaining friends with Italy.  They opposed the  Italians in the League of Nations, as J.M. Roberts observes, "feebly and half- heartedly because they did not want to alienate a possible ally against Germany"  (Roberts, 845).  Suppose Italy, France, and Britain had retained a certain common  interest.  Would Hitler have been able to get away with his remarkable bluffing  bullying in the later Thirties?

Comment: 

No plagiarism.  The writer properly acknowledges the one use of Roberts's ideas.   (Note that the writer has chosen to use only one idea from the source and has  integrated that idea into his or her own argument.)