如何从laravel中的with relation的第一个表中选择特定的列？

$users = User::with(['posts' => function ($query) {
    $query->select('id', 'title');
}])->get();

$users = User::with(['posts' => function ($query) {
    $query->select('id', 'title');
}, 'comments' => function ($query) {
    $query->select('id', 'content');
}])->get();