命名空间中怎么实现全部单词替换

命名空间中如何实现全部单词替换
DataCleaner.inc.php:

PHP code

<!--Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/--><?php    namespace DataCleaner;    class Clean {        function RemoveProfanity($text) {            $badwords = array(                                "idiotic" => "shortsighted",                                "moronic" => "unreasonable",                                "insane" => "illogical"                             );                        // Remove bad words            foreach ($badwords as $key => $value) {                if (strpos($text, $key) !== false)                    return str_replace($key, $value, $text);            }        }    }?>

Library.inc.php:

PHP code

<!--Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/--><?php    namespace Library;    class Clean {        function FilterTitle($text) {            // Trim white space and capitalize first word            return ucfirst(trim($text));        }    }?>

index.php:

PHP code

<!--Code highlighting produced by Actipro CodeHighlighter (freeware)http://www.CodeHighlighter.com/--><?php    include "DataCleaner.inc.php";    include "Library.inc.php";        $data = new DataCleaner\Clean();    $library = new Library\Clean();        $title = "the moronic sun also rises idiotic insane";        printf("Title before filters: %s<br />", $title);        $title = $data->RemoveProfanity($title);    printf("Title after Data::Clean: %s<br />", $title);        $title = $library->FilterTitle($title);    printf("Title after Library::Clean: %s<br />", $title);?>

输出：
Title before filters: the moronic sun also rises idiotic insane
Title after Data::Clean: the moronic sun also rises shortsighted insane
Title after Library::Clean: The moronic sun also rises shortsighted insane


怎么实现把所有的
"idiotic" => "shortsighted",
"moronic" => "unreasonable",
"insane" => "illogical"
这些词都替换成相应的单词？？

------解决方案--------------------
foreach ($badwords as $key => $value) {
if (strpos($text, $key) !== false)
return str_replace($key, $value, $text);
}
=================

修改为
return strtr($text, $badwords);