David Stern expressed his gratitude to Houston Rockets when he visited Guangzhou on Friday.

Stern moved up and down his left hand with two fingers extended in front of the fans, but no one could know what he means at that moment.

But after less than a second could people recognize the sign language meant "rocket" . Then he bent his thumb twice to conclude his speech with a perfect ending: "Thank You Rockets!"

The NBA commissioner learnt his sign language from a group of deaf Children on Friday. In the southern city of Guangzhou, NBA gave these children a chance to feel the real NBA stars. One hour training section was called "NBA Cares" . The result was obvious: the kids had a happy hour while the NBA commissioner learnt his sign language.

Rockets is the team Chinese star Yao Ming has played since 2002, also called the year of Yao. NBA has enjoyed an ever growing profit in China since.