if ( is_category() ) {
$title = sprintf( __( 'Category: %s' ), single_cat_title( '', false ) );
} elseif ( is_tag() ) {
$title = sprintf( __( 'Tag: %s' ), single_tag_title( '', false ) );
} elseif ( is_author() ) {
$title = sprintf( __( 'Autor: %s' ), '<span class="vcard">' . get_the_author() . '</span>' );
}
//directory: wp-includes
//file: general-template.php
//find function: get_the_archive_title() change: