سلام و خسته نباشید :
function Person(name , age , heigh , weight){ this.name = name; this.age = age; this.heigh = heigh; this.weight = weight; this.sayName = function(){ return this.name[0].toUpperCase() + this.name.slice(1); } this.sayHeight = function(){ this.heigh = this.heigh / 100; return this.heigh + "m"; } this.sayBmi = function(){ let bm = parseInt(this.weight / (Math.pow(this.weight , 2))); return bm; } } let milad = new Person("milad" , 31 , 185 , 89); console.log(sayName()); console.log(this.age); console.log(sayHeight()); console.log(sayBmi());