Sooner or later, almost all writers quote or closely paraphrase what others have written. For example:

几乎所有作者都会引用或者意译其它人所写的内容，这个只是早晚的事。例如：

• Andy, putting together a newsletter on his home computer, reprints an editorial he likes from a daily newspaper.

   

   

• 安迪在电脑前拼凑了一份简报，从他喜欢的报纸上转载了一篇社论。

   

• Phil, a biographer and historian, quotes from several unpublished letters and diaries written by his subject.

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• Regina, a freelance writer, closely paraphrases two paragraphs from the Encyclopedia Britannica in an article she's writing.

• Sylvia, a poet, quotes a line from a poem by T.S. Eliot in one of her own poems.

• Donnie, a comedian, writes a parody of the famous song "Blue Moon" he performs in his comedy act.

Assuming the material quoted in these examples is protected by copyright, do Phil, Regina, Sylvia, Andy, and Donnie need permission from the author or other copyright owner to use it? It may surprise you to learn that the answer is "not necessarily."

Under the "fair use" rule of copyright law, an author may make limited use of another author's work without asking permission. Fair use is based on the belief that the public is entitled to freely use portions of copyrighted materials for purposes of commentary and criticism. The fair use privilege is perhaps the most significant limitation on a copyright owner's exclusive rights. If you write or publish, you need a basic understanding of what is and is not fair use.

Subject to some general limitations discussed later in this article, the following types of uses are usually deemed fair uses:

以下的几种情形常常视为合理利用：

• Criticism and comment --用于批评或者评论

•  for example, quoting or excerpting a work in a review or criticism for purposes of illustration or comment. 例如，在评论或者批评中引用某篇文章的一段话作为例子或者进行评价。

• News reporting --新闻报道

  for example, summarizing an address or article, with brief quotations, in a news report.

• Research and scholarship --用于研究或者是学术需要

• for example, quoting a short passage in a scholarly, scientific, or technical work for illustration or clarification of the author's observations.

• Nonprofit educational uses --用于非赢利性教育

  for example, photocopying of limited portions of written works by teachers for classroom use.

• Parody -- 恶搞

• that is, a work that ridicules another, usually well-known, work by imitating it in a comic way.

In most other situations, copying is not legally a fair use. Without an author's permission, such a use violates the author's copyright.

Non-commercial use is often fair use. Violations often occur when the use is motivated primarily by a desire for commercial gain. The fact that a work is published primarily for private commercial gain weighs against a finding of fair use. For example, using the Bob Dylan line "You don't need a weatherman to know which way the wind blows" in a poem published in a small literary journal would probably be a fair use; using the same line in an advertisement for raincoats probably would not be.

Benefit to the public may be fair use. A commercial motive doesn't always disqualify someone from claiming a fair use. A use that benefits the public can qualify as a fair use, even if it makes money for the user.

For example, in its advertising a vacuum cleaner manufacturer was permitted to quote from a Consumer Reports article comparing vacuum cleaners. Why? The ad significantly increased the number of people exposed to the Consumers Reports' evaluations and thereby disseminated helpful consumer information. The same rationale probably applies to the widespread practice of quoting from favorable reviews in advertisements for books, films, and plays.

The purpose and character of your intended use of the material involved is the single most important factor in determining whether a use is a fair use. The question to ask here is whether you are merely copying someone else's work verbatim or instead using it to help create something new.

Rule 2: Are Your Competing With the Source You're Copying From?

准则 2：你的内容与拷贝的内容是否有竞争关系？

Without consent, you ordinarily cannot use another person's protected expression in a way that impairs (or even potentially impairs) the market for his or her work.

For example, say Nick, a golf pro, writes a book on how to play golf. He copies several brilliant paragraphs on putting from a book by Lee Trevino, one of the greatest putters in golf history. Because Nick intends his book to compete with and hopefully supplant Trevino's, this use is not a fair use.

Rule 3: Giving the Author Credit Doesn't Let You Off the Hook

准则3：标明了使用材料的来源并不表明你就可以免责

Some people mistakenly believe that they can use any material as long as they properly give the author credit. Not true. Giving credit and fair use are completely separate concepts. Either you have the right to use another author's material under the fair use rule or you don't. The fact that you attribute the material to the other author doesn't change that.

Rule 4: The More You Take, the Less Fair Your Use Is Likely to Be

准则 4：你取得越多，有可能你的使用就越不公平

The more material you take, the less likely it is that your use will be a fair use. As a general rule, never: quote more than a few successive paragraphs from a book or article, take more than one chart or diagram, include an illustration or other artwork in a book or newsletter without the artist's permission, or quote more than one or two lines from a poem.

Contrary to what many people believe, there is no absolute word limit on fair use. For example, copying 200 words from a work of 300 words wouldn't be fair use. However, copying 2000 words from a work of 500,000 words might be fair. It all depends on the circumstances.

To preserve the free flow of information, authors have more leeway in using material from factual works (scholarly, technical, and scientific works) than to works of fancy such as novels, poems, and plays.

Rule 5: The Quality of the Material Used Is as Important as the Quantity

准则 5： 使用的材料的质量与数量同样重要

The more important the material is to the original work, the less likely your use of it will be considered a fair use.

In one famous case, The Nation magazine obtained a copy of Gerald Ford's memoirs before their publication. In the magazine's article about the memoirs, only 300 words from Ford's 200,000-word manuscript were quoted verbatim. The Supreme Court ruled that this was not a fair use because the material quoted (dealing with the Nixon pardon) was the "heart of the book ... the most interesting and moving parts of the entire manuscript," and that pre-publication disclosure of this material would cut into value or sales of the book.

In determining whether your intended use of another author's protected work constitutes a fair use the golden rule: Take from someone else only what you wouldn't mind someone taking from you.

When it comes to fair use, unpublished works are inherently different from published works. Publishing an author's unpublished work before he or she has authorized it infringes upon the author's right to decide when and whether the work will be made public.

Some courts in the past held that fair use never applies to unpublished material. However, in 1991 Congress amended the fair use provision in the Copyright Act to make clear that the fact that a work is unpublished weighs against fair use, but is not determinative in and of itself.

For more detailed information on fair use and copyrighted material, see Getting Permission: How to License & Clear Copyrighted Materials Online & Off, by Richard Stim (Nolo).