Google's search engine normally accepts queries as a simple text, and breaks up the user's text into a sequence of search terms, which will usually be words that are to occur in the results, but one can also use operators, such as: quotations marks for a phrase, a prefix such as for qualified terms, or one of several advanced operators, such as "site:". The webpages of "Google Search Basics"describe each of these additional queries and options . Google's Advanced Search web form gives several additional fields which may be used to qualify searches by such criteria as date of first retrieval. All advanced queries transform to regular queries, usually with additional qualified term.