请作答72题。
WebSQL is a SQL-like （71） language for extracting information from the web. Its capabilities for performing navigation of web （72） make it a useful tool for automating several web-related tasks that require the systematic processing of either all the links in a （73）, all the pages that can be reached from a given URL through （74） that match a pattern, or a combination of both. WebSQL also provides transparent access to index servers that can be queried via the Common （75） Interface.
