Except for pure fiction, nearly all writing is based to some extent on other sources. Ethics and the laws of copyright require authors to identify their sources by using citations within the body of an assignment and a reference list at the end. The purpose of this is to allow the reader to locate the original material and to examine it. Accuracy and consistency is therefore very important when citing.
Failure to give CREDIT to sources consulted, even if they are paraphrased or reworded, is PLAGIARISM. The University may impose penalties on students who plagiarise another's work, whether it is intentional or not.