渲染登陆模板

Question

<?php
namespace app\index\controller;
use app\index\controller\Base;（Import 'app\index\controller\Base' is not necessaryUsage of statement use was not found.）
class Index extends Base
{
   public function index()
   {
       return $this -> view -> fetch();
   }
}

控制器下index.php出现错误Import 'app\index\controller\Base' is not necessary，Usage of statement use was not found.

和视屏代码一样，渲染不了登陆模板，并且将问答社区的方法都试过了也不行