The `comment_footer_die()` function in WordPress displays an error message at the bottom of the comments page when certain conditions aren't met, such as length or spam content
The `cancel_comment_reply_link()` function in WordPress generates HTML content for a "cancel" comment reply link, displaying a custom message if specified
The `comment_type()` function in WordPress displays the type of the current comment as either a regular comment, trackback, or pingback using default or custom text