你需要使用 belongTo 得分模型中的关系。

public function user(){
   return $this->belongsTo(User::class,'subject_id ');
}

现在你可以得到这样的用户名。

$scores = Score::with('lead','subject')->with('user')->where('lead_id','=',$id)->get();

从聊天讨论中发现你 belongsTo 关系 Subject 以及 User 模型。您正在使用 subject_id 在你的分数表和 Score 模型具有 belongsTo 关系 Subject 模型。所以，是的，你可以像这样获取用户的详细信息

{{$score->subject->user->name}}

索引.php

$posts = Posts::read_all();

      foreach ( $posts as $post )
 {
         echo $post->post_name ."<br>";
          echo $post->post_text ."<br>";

$categories_array = Posts::get_cats_by_post_id($post->id);

foreach ($categories_array as $category)
{
    echo "&bull;". $category->category_name ."<br>";
}

}

课后

公共静态函数get_cats_by_post_id（$id）{$db=new database（）；

$sql = "SELECT  cats_to_posts.cats_id
        FROM    cats_to_posts
        WHERE   cats_to_posts.post_id = {$id}";

$result = $db->exe_query($sql);

$cat_id_array = array(); // stores array of category ids that match post ids

while ( $record = $result->fetch_object() )
{
    $cat_id_array[] = $record;
}

$cat_name_array = array(); // stores array of category names that match category ids
foreach($cat_id_array as $cat_id)
{
    $new_sql = "SELECT  category_name
                FROM    categories
                WHERE   id = ". $cat_id->cats_id;

    $new_result = $db->exe_query($new_sql);

    while ( $new_record = $new_result->fetch_object() )
    {
        $cat_name_array[] = $new_record;
    }

}

return $cat_name_array;

}
试试这个希望，这样就行了。