Windows 命令行运行git提示ObjectNotFound

新系统运行git命令提示：

git : The term 'git' is not recognized as the name of a cmdlet, function, script file, or operable program. Check the
spelling of the name, or if a path was included, verify that the path is correct and try again.
At line:1 char:1
+ git clone https://gitee.com/macrozheng/mall.git
+ ~~~
    + CategoryInfo          : ObjectNotFound: (git:String) [], CommandNotFoundException
    + FullyQualifiedErrorId : CommandNotFoundException