 Complete the following phrase:  Combining Cai Yuns impressive speed with his regular partner Fu Haifengs impressive power, Cai and Fu have been one of the worlds leading mens doubles teams since 2004. They have won numerous top tier events on the world circuit including the venerable All England Open Championships in 2005 and 2009. They have won the BWF World Championships 4 times in 2006, 2009, 2010 and 2011, becoming the first Mens Doubles pair to achieve this feat. Cai and Fu have helped China win five consecutive Thomas Cup Mens Team World Badminton Championships 2004, 2006, 2008, 2010, and 2012 and six consecutive Sudirman Cup World Team Championships 2005, 2007, 2009, 2011, 2013 and 