咩叫US Open

US Open is 美國網球公開賽

The United States Open tennis tournament, commonly referred to as the US Open, is the fourth and final event of the Grand Slam tennis tournaments. It is held annually in August and September over a two week period (the weeks prior to and following Labor Day weekend). The main tournament consists of five championships: men's and women's singles, men's and women's doubles, and mixed doubles, with additional tournaments for senior, junior, and wheelchair players. Since 1978, the tournament has been played on acrylic hard court at the USTA Billie Jean King National Tennis Center at Flushing Meadows-Corona Park in the Queens borough of New York City. The complex was renamed after King during the 2006 US Open. King is a pioneer in women's tennis and the founder of the Women's Tennis Association(WTA), the Women's Sports Foundation and World Team Tennis (WTT), which she founded with her former husband, Larry King.

The US Open is different from the other 3 Grand Slam tournaments in that there are final set tiebreaks. In the other three majors, the fifth set for the men and the third set for the women continues until someone wins by two games.

In 2006, the US Open became the first Grand Slam tournament to implement instant replay review of calls, using Hawk-Eye. Available only on the stadium courts (Ashe and Armstrong), each player is allowed two challenges per set plus one additional challenge during a tiebreak, but is not penalized with the loss of a challenge if the challenge turns out to be correct. Once the challenge is made, the official review (a 3D computer simulation based on multiple high-speed video cameras) is shown to the players, umpires, and audience on the stadium video boards and to the television audience at the same time. The system is said to be accurate to within 5 millimeters. During the 2006 US Open, 30.5% of men's challenges were upheld and 35.85% of women's challenges were upheld