Extreme Programming (XP) is a discipline of software development with（）of simplicity， communication， feedback and courage. Successful software development is a team effort - not just the development team， but the larger team consisting of customer， management and developers. XP is a simple process that brings these people together and helps them to succeed together. XP is aimed primarily at object-oriented projects using teams of a dozen or fewer programmers in one location. The principles of XP apply to any（）project that needs to deliver quality software rapidly and flexibly.
An XP project needs a （）customer to provide guidance. Customers， programmers， managers， are all working （） to build the system that’s needed. Customers - those who have software that needs to be developed - willlearn simple， effective ways to（）what they need， to be sure that they are getting what they need， and to steer the project to success.