Consider the following examples of paraphrasing from Rules for Writers , Second Edition. If the existence of a signing ape was unsettling for linguists, it was also startling news for animal behaviorists. It too must be worded and structured differently from the original and cited. You should enclose any key words or phrases from the original source in quotation marks. Any summary or paraphrase of another writer's material must be documented.
Unintentional plagiarism is still plagiarism.
Often, students plagiarize without meaning to do so. Ignorance and wrongful assumptions, however, are no excuse. In an informal essay, an internal citation to introduce direct quotes, paraphrased or summarized material may be sufficient documentation. However, in a formal paper all quoted, paraphrased, or summarized material must be documented, even if you have used an internal citation in the text. If in doubt, ask your professor whether or not internal citation is sufficient documentation for a specific assignment.