关键字： break case catch continue default delete do else finally for function if in instanceof new return switch this throw try typeof var void while with

保留字：abstract boolean byte char class const debugger double enum export extends final float goto implements import int interface long native package private protected public short static super synchronized throws transient volatile

赋值数字了之后，你再调用这个变量时，就相当于调用这个数字

那是给你定义的变量赋值

var