When writing any kind of paper or homework at the university I am supposed to give references for my citations. At the same time, sources like Wikipedia are not considered good for university level. Now let's say I am writing about malware, and I want to give definition about virus. Wikipedia has a good explanation, but I obviously cannot just copy without references (right?), and to give reference to Wikipedia is considered unacceptable.
So how am I supposed to give reference to such an item? Am I supposed to change the sentence in such a way that it cannot be tracked where I took it from?