为什么这样写不行

 System.out.println("three=one+two==>"+three=one+two);

       System.out.println("three+=one==>"+three+=one);

        System.out.println("three-=one==>"+three-=one);

        System.out.println("three*=one==>"+three*=one);

        System.out.println("three/=one==>"+three/=one);

        System.out.println("three%=one==>"+three%=one);

    }

            }