如何调用子构造函数方法？

class ParentClass {
  constructor(name) {
    this.name = name;
  }

  sayHello() {
    console.log(`Hello, ${this.name}!`);
  }
}

class ChildClass extends ParentClass {
  constructor(name, age) {
    super(name); // 调用父类的构造函数
    this.age = age;
  }

  introduce() {
    console.log(`My name is ${this.name} and I'm ${this.age} years old.`);
  }
}

const child = new ChildClass("Alice", 25);
child.sayHello(); // 输出：Hello, Alice!
child.introduce(); // 输出：My name is Alice and I'm 25 years old.