File Content: default-form-content.php <?php $email_label = esc_html__('Email address', 'mailchimp-for-wp'); $email_placeholder_attr = esc_attr__('Your email address', 'mailchimp-for-wp'); $signup_button_value = esc_attr__('Sign up', 'mailchimp-for-wp'); $content = "<p>\n\t<label for=\"email\">{$email_label}: \n"; $content .= "\t\t<input type=\"email\" id=\"email\" name=\"EMAIL\" placeholder=\"{$email_placeholder_attr}\" required>\n</label>\n</p>\n\n"; $content .= "<p>\n\t<input type=\"submit\" value=\"{$signup_button_value}\">\n</p>"; return $content; Submit