Two-time Grand Slam Champion Chinese tennis player Li Na (L) signs for young tennis players during a youth tennis clinic in Mahattan of New York, the United States, July 18, 2019. Two-time Grand Slam Champion Li Na will be kicking off her upcoming International Tennis Hall of Fame (ITHF) induction weekend by sharing her love of the game with some of the sport's youngest players and fans. (Xinhua/Wang Ying)