[PHP] A beginner´s question

[Eduardo]

Hi, I am Eduardo, a new PHP programmer and an old Cobol veteran.
I know that
        $tastes=$_POST["tastes"]; 
moves the content of "tastes" from
        <p><textarea rows="5" name="tastes" cols="28"></textarea></p>
to
        $tastes


How do I move the content of $tastes to X of
        echo "<textarea rows="5" cols="28" readonly name=X>\n";
?

Thanks, 
Eduardo