add data to laravel many to many relationship

1$employee = employee::find(1);
2
3$salary1 = new Salary;
4$salary->amount = '123456789';
5$salary->payment_date = '15/07/2020';
6
7$salary2 = new Salary;
8$salary->amount = '123456789';
9$salary->payment_date = '16/07/2020';
10
11$employee = $employee->salary()->saveMany([$salary1, $salary2]);

11. $user->roles()->attach($roleId);
2
32. you may also pass an array of additional data to be inserted 
4$user->roles()->attach($roleId, ['expires' => $expires]);
5
63. // Detach a single role from the user...
7$user->roles()->detach($roleId);
8
94. // Detach all roles from the user...
10$user->roles()->detach();
11
125. Any IDs that are not in the given array will be removed from the intermediate
13	table
14$user->roles()->sync([1, 2, 3]);
15
166. If you need to update an existing row in your pivot table, you may use 
17  updateExistingPivot method. This method accepts the pivot record foreign 
18  key and an array of attributes to update:
19
20$user->roles()->updateExistingPivot($roleId, $attributes);