buildadmin/app/admin/lang/en.php

<?php
return [
    'Username'                                   => 'User Name',
    'Password'                                   => 'Password',
    'Captcha'                                    => 'Captcha',
    'CaptchaId'                                  => 'Captcha Id',
    'Please enter the correct verification code' => 'Please enter the correct verification code!',
];