Test all pass

app/Http/Controllers/CountryController.php

@@ -9,7 +9,7 @@ class CountryController extends Controller
     public function index()
     {
         // TASK: load the relationship average of team size
-        $countries = Country::all();
+        $countries = Country::withAvg('teams', 'size')->get();;
 
         return view('countries.index', compact('countries'));
     }

app/Http/Controllers/ProjectController.php

@@ -3,14 +3,16 @@
 namespace App\Http\Controllers;
 
 use Illuminate\Http\Request;
+use Illuminate\Support\Facades\Auth;
+use Illuminate\Support\Facades\DB;
 
 class ProjectController extends Controller
 {
     public function store(Request $request)
     {
         // TASK: Add one sentence to save the project to the logged-in user
         //   by $request->project_id and with $request->start_date parameter
-
+        Auth::user()->projects()->attach($request->project_id, ['start_date' => $request->start_date]);
         return 'Success';
     }
 }

app/Http/Controllers/UserController.php

@@ -8,7 +8,7 @@ class UserController extends Controller
 {
     public function index()
     {
-        $users = User::all();
+        $users = User::has('projects', '>=', 1)->get();
 
         return view('users.index', compact('users'));
     }

app/Models/Attachment.php

@@ -14,5 +14,6 @@ class Attachment extends Model
     public function attachable()
     {
         // TASK: fill in the code to make it work
+        return $this->morphTo('attachable', 'attachable_type', 'attachable_id');
     }
 }

app/Models/Role.php

@@ -14,6 +14,6 @@ class Role extends Model
     public function users()
     {
         // TASK: fix this by adding a parameter
-        return $this->belongsToMany(User::class);
+        return $this->belongsToMany(User::class, 'users_roles');
     }
 }

app/Models/Task.php

@@ -4,6 +4,7 @@
 
 use Illuminate\Database\Eloquent\Factories\HasFactory;
 use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\HasMany;
 
 class Task extends Model
 {
@@ -15,4 +16,10 @@ public function user()
     {
         return $this->belongsTo(User::class, 'users_id');
     }
+
+    public function comments(): HasMany
+    {
+        // TASK: fix this by adding a parameter
+        return $this->hasMany(Comment::class);
+    }
 }

app/Models/Team.php

@@ -14,7 +14,7 @@ class Team extends Model
     public function users()
     {
         // TASK: fix this by adding some extra code
-        return $this->belongsToMany(User::class);
+        return $this->belongsToMany(User::class, 'team_user:position,created_at');
     }
 
 }

app/Models/User.php

@@ -7,6 +7,7 @@
 use Illuminate\Foundation\Auth\User as Authenticatable;
 use Illuminate\Notifications\Notifiable;
 use Laravel\Sanctum\HasApiTokens;
+use Illuminate\Database\Eloquent\Relations\HasMany;
 
 class User extends Authenticatable
 {
@@ -42,15 +43,16 @@ class User extends Authenticatable
         'email_verified_at' => 'datetime',
     ];
 
-    public function tasks()
+    public function tasks(): HasMany
     {
         // TASK: fix this by adding a parameter
-        return $this->hasMany(Task::class);
+        return $this->hasMany(Task::class, 'users_id');
     }
 
     public function comments()
     {
         // TASK: add the code here for two-level relationship
+        return $this->hasManyThrough(Comment::class, Task::class, 'users_id');
     }
 
     public function projects()

resources/views/tasks/index.blade.php

@@ -1,5 +1,5 @@
 <ul>
     @foreach ($tasks as $task)
-        <li>{{ $task->name }} ({{ $task->user->name }})</li>
+        <li>{{ $task->name }} ({{ $task->user->name ?? '' }})</li>
     @endforeach
 </ul>