请问这种写法对不对

function calculate(num1,num2){

        return {

            'add':function(){

             return num1+num2;

            },

            'subtrat':function(){

                return  num1*num2;

            },

            'multiplay':function(){

                return  num1/num2;

            },

            'divide':function(){

                return num1-num2;

            }

        }

    }

    console.log(calculate(1,2).add());