How to enable Unit test in Visual Studio

In VS2008, when I right click a source file, there is a menu item "Create Unit test", but on another PC w/ VS2005, when I right click, there is no such menu item. How to make the Unit Test in context menu in VS2005? I guess probably some option is not enabled. thanks

开发者_如何转开发VS2005 pro does not have Unit test integrated. see VS 2005 Test Project Not Opening. I guess I need install some test framework like NUnit in VS2005

VS2005 pro does not have Unit test integrated. see VS 2005 Test Project Not Opening. so need install some test framework like NUnit