Plagiarism--the unacknowledged borrowing of materials from another source--happens when we quote or paraphrase from a source, which are the only two ways to use sources in our writing.
It’s easy to avoid problems when quoting a source. Simply make sure that you (1) introduce who is speaking, (2) bracket the exact words in quotation marks, and (3) add a citation.
A paraphrase means translating the quote into your own phrases. A paraphrase doesn’t mean putting a quotation entirely in your own words. That is impossible. You will have to repeat key words. A successful paraphrase means to translate the quotation into your own way of writing or speaking