错误消息-Laravel 5.2

有人能告诉我如何让我的"找不到页面"或其他消息吗？例如，如果有人在浏览器中写了一个我的项目中不存在的链接，而不是显示标准错误页面（哇，出了问题，找不到View[bla.bla]），而是显示我指定的页面？

<?php

Route::get('sendemail', 'EmailController@sendEmail');
Route::get('test', 'AuthController@getTest');
Route::get('napravisiadmin', 'ClassbookController@getIndex');
Route::group(['middleware' => ['web']], function () {
    Route::group(['middleware' => ['guest']
    ], function () {
        Route::get('login', 'AuthController@getLogin');
        Route::post('login', 'AuthController@postLogin');
    });
    Route::get('logout', 'AuthController@getLogout');

    //Admin
    Route::group(['middleware' => ['auth', 'auth.admin']
    ], function () {
        Route::group([
            'prefix' => 'admin',
            'namespace' => 'Admin'
        ], function () {
            Route::controller('student', 'StudentsController');
            Route::controller('profile', 'ProfilesController');
            Route::controller('class', 'ClassesController');
            Route::controller('subjects', 'SubjectsController');
            Route::controller('teacher', 'TeachersController');
            Route::controller('marktype', 'MarkTypeController');
            Route::controller('rules', 'RuleController');
            Route::get('{slug?}', 'PageController@getView');
        });
    });
    //Admin

    //Student
    Route::group([
        'middleware' => ['auth', 'auth.student'],
        'prefix' => 'stu',
        'namespace' => 'Stu'
    ], function () {
        Route::get('{slug?}', 'StuController@getView');
    });
    //Student

    //Teacher
    Route::group([
        'middleware' => ['auth', 'auth.teacher'],
        'prefix' => 'educator',
        'namespace' => 'Educator'
    ], function () {
        Route::get('edit/{id}', 'AccountController@getEdit');
        Route::post('edit/{id}', 'AccountController@saveEdit');
        Route::get('account', 'AccountController@getView');
        Route::get('class-subject', 'AccountController@getClassSubject');
        Route::get('add-mark', 'AccountController@getAddMark');
        Route::post('mark', 'AccountController@postAddMark');
        Route::get('added', 'AccountController@marksList');
        Route::get('statistics', 'AccountController@marksInTable');
        Route::get('personalemails', 'PersonalEmailController@getView');
        Route::post('personalemails', 'PersonalEmailController@personalEmail');
    });
    //Teacher
});

Route::get('{slug?}', 'PageController@getView');