angular 动态表单问题

Question

 profileForm = this.fb.group({
    firstName: [''],
    lastName: [''],
    address: this.fb.group({
      street: [''],
      city: [''],
      state: [''],
      zip: ['']
    }),
  });

如果初始的结构是这样的
我想动态的往adress中addControl 应该怎么写呢

不是this.profileForm.address.addControl() 么