The penalties for plagiarism can range from failing the assignment, to expulsion from university.
Plagiarism is --
Do not --
It is better to cite too often, than cite too little. Check with your professor if you're not sure.
If you need help with citations or citation styles talk to a librarian, your professor, or someone in the writing center.
Plagiarism devalues your degree, is a form of self-sabotage, and corrupts the scholarly method.