How to use echo as an output with HTML format

Question

I need to print an error which contain html format which in my case is <strong>. here's my code that i want to produce the output

if (empty($namabelakang)){
        $errors[] = "<strong>Nama Belakang</strong> tidak boleh kosong";
    }

and here's the one which i use to print:

foreach($errors as $error){
        echo clean($error)."<br>";
    }

It's not print as i'm expecting, it print

<strong>Nama Belakang</strong> tidak boleh kosong

Rather than:

Nama Belakang tidak boleh kosong

Please help me how can I fix it? here's the code for clean function:

function clean($data) {
    $data = trim($data);
    $data = stripslashes($data);
    $data = htmlspecialchars($data);
    return $data;
}

Answer 1

   function clean($data) {
    $data = trim($data);
    $data = stripslashes($data);
    $data = htmlspecialchars($data);
    $data = str_replace(array("&lt;strong&gt;", "&lt;/strong&gt;"), array("<strong>", "</strong>"), $data);
    return $data;
}