Put in quotations everything that comes directly from the text, with proper attibution .
When you paraphrase, do NOT just rearrange the sentences or replace a few words. You will summarize/express the original idea/argument with your own words to demonstrate your own understanding, with proper attribution.
Examples of acceptable and unacceptable paraphrases:
You do not need to cite your source if the information is considered as "common knowledge." Common knowledge is any information that the average, educated reader would accept as reliable without having to look it up. However, there is no clear boundary on what is considered as common knowledge.