關鍵字： 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

賦值數字了之后，你再調用這個變量時，就相當于調用這個數字

那是給你定義的變量賦值

var