[7.1.含义与定义形式](7.1.%E5%90%AB%E4%B9%89%E4%B8%8E%E5%AE%9A%E4%B9%89%E5%BD%A2%E5%BC%8F.md) [7.2.变量的命名规则](7.2.%E5%8F%98%E9%87%8F%E7%9A%84%E5%91%BD%E5%90%8D%E8%A7%84%E5%88%99.md) [7.3.变量的4种基本操作](7.3.%E5%8F%98%E9%87%8F%E7%9A%844%E7%A7%8D%E5%9F%BA%E6%9C%AC%E6%93%8D%E4%BD%9C.md) [7.4.变量传值（难点）](7.4.%E5%8F%98%E9%87%8F%E4%BC%A0%E5%80%BC%EF%BC%88%E9%9A%BE%E7%82%B9%EF%BC%89.md) [7.5.预定义变量](7.5.%E9%A2%84%E5%AE%9A%E4%B9%89%E5%8F%98%E9%87%8F.md) [7.6.可变变量](7.6.%E5%8F%AF%E5%8F%98%E5%8F%98%E9%87%8F.md)