Wordpress String Translate

gistfile1.php

function stringtranslate_filter_gettext( $translated, $original, $domain ) {
    $strings = array(
        'Post Comment' => 'Hinterlassen Sie eine Antwort',
    );
    if ( isset( $strings[$original] ) ) {
        $translations = &get_translations_for_domain( $domain );
        $translated = $translations->translate( $strings[$original] );
    }
    return $translated;
}
add_filter( 'gettext', 'stringtranslate_filter_gettext', 10, 3 );