Function.prototype.myApply = function (arg) {
  arg.fn = this;
  arg.fn();
  delete arg.fn;
  };

  const rose = {
  name: 'rose',
  greet: function() {
  console.log(`Hello, I am ${this.name}`)
  }
  };

  const jack = {
  name: 'jack'
  }

  rose.greet();
  rose.greet.myApply(jack);