Example translation function

functions.php

<?php
//Please do not include the opening PHP tag if you already have one.

function mycustom_filter_gettext( $translated, $original, $domain ) {
 
    // This is an array of original strings
    // and what they should be replaced with
    $strings = array(
	'The following events do not require payment at this time and will not be billed during this transaction. Billing will only occur after the attendee has been approved by the event organizer. You will be notified when your registration has been processed. If this is a free event, then no billing will occur.' => 'Custom Text Here',
        // Add some more strings here
    );
 
    // See if the current string is in the $strings array
    // If so, replace its translation
    if ( isset( $strings[$original] ) ) {
        // This accomplishes the same thing as __()
        // but without running it through the filter again
        $translations = get_translations_for_domain( $domain );
        $translated = $translations->translate( $strings[$original] );
    }
 
    return $translated;
}
 
add_filter( 'gettext', 'mycustom_filter_gettext', 10, 3 );