Another form of plagiarism is a word-for-word copying of someone else's work, in whole or in part, without appropriate acknowledgement, whether that work be a journal or magazine article, a portion of a book, a newspaper piece, another student's paper, or any other composition not your own.
Any such verbatim use of another's work must be acknowledged by (1) appropriate indention or enclosing all such copied portions in quotation marks and by (2) giving the original source in a footnote. As a general rule, you should make very little use of directly quoted matter in your research paper. If you do not know how to footnote properly, ask your instructor for guidance.