短文改错（共10小题，每小题1分，满分10分）

Not all people like to work and everyone likes to play. All over the world men and woman, boys and girls enjoy sports. Since long ago, many adults and children called their friends together to spend hours, even days play games. One of the reasons people like to play is that sports help them to live happy. In other words, they help to keep people strong and feel well. When people are playing games, they move a lot .That is how sports are good activities for their health. Having fun with their friends make them happy .Many people enjoy sports by watching others play. In American big cities, thousands sell tickets to watch football or basketball games.

用于获得字符串Str从第2个字符开始的3个字符的函数是______。

A．Mid(Str,2,3)

B．Middle(Str,2,3)

C．Right(Str,2,3)

D．Left(Str,2,3)