Template form

<form #userForm="ngForm" (ngSubmit)="onFormSubmitted(userForm)">
  <label>
    <span>Name</span>
    <input type="text" name="name" placeholder="Name" [(ngModel)]="user.name" required>
  </label>
  <div>
    <label>
      <span>Email</span>
      <input type="email" name="email" placeholder="Email" [(ngModel)]="user.email" required>
    </label>
  </div>
  <div ngModelGroup="address">
  <label>
    <span>Country</span>
    <input type="text" name="country" placeholder="Country" [(ngModel)]="user.address.country" required>
  </label>
  <div>
    <label>
      <span>City</span>
      <input type="text" name="city" placeholder="City" [(ngModel)]="user.address.city" required>
    </label>
  </div>
  </div>
  <input type="submit" [disabled]="userForm.invalid">
</form>