To put your name on a piece of work any part of which is not yours is plagiarism, unless that piece is clearly marked and the work from which you have borrowed is fully identified.
Plagiarism is a form of theft.
Taking words, phrasing, sentence structure, or any other element of the expression of another person s ideas, and using them as if they were yours, is like taking from that person a material possession, something he or she has worked for and earned. Even worse is the appropriation of someone else s ideas. Paraphrase, therefore, without proper documentation, is theft, perhaps of the worst kind. Here, a person loses not a material possession, but something of what characterized him or her as an individual. Your responsibility, when you put your name on a piece of work, is simply to distinguish between what is yours and what is not, and to credit those who have in any way contributed.