They are not substitutes for your ideas and they do not stand by themselves. See the link at the bottom of this page, "How to cite this page," for more information.
It is often useful to apply some interpretive phrasing after a quotation, to show the reader that the you are explaining the quotation and that it supports your argument: Note that the particular verb you choose helps orient your reader toward your opinion of the statement. At the beginning of many of the Holmes stories, Doyle takes care to capture the reader's interest by proclaiming that the story just getting under way is an especially noteworthy or remarkable one.
You won't do all of these each time, but you should usually name the author. What does the quotation mean and how does it help establish the point you are making? Quotations are like examples: discuss them to show how they fit in with your thesis and with the ideas you are presenting.
Remember: quotations support or illustrate your own points. Note: For Web articles, omit information not available, such as author, article date, site name, etc. Always include article title, date of access, and URL at the very minimum.
Check the appropriate style guide for guidelines, e.g. Here are some guidelines for MLA style citation: EXPLAIN: Make sure to explain your quotes.
Provide analysis that ties them back to your main idea / topic sentence.
Sometimes it’s necessary to have a quotation within a quotation.
When it happens, we use single quotation marks for the interior quotation.
A good general guideline is that 2/3 of the paper is your ideas and 1/3 of the paper is outside sources.
Verify with your instructor if you feel the assignment requires more or less information from sources.