Put link into php

i want to put link into a sentence that are stored in variable.. how to put the link? because i try use echo..but it did not work..

here is my code:

if($_POST['rb_elt_accommodation']开发者_Python百科=="Yes") 
$accomodation_val .= "Participants must deal directly with the hotel. Please call the hotel direct at +xxxxxx. Details on accomodation booking are available"echo '<a href="http://abc.com">here</a>.'";

if ($_POST['rb_elt_accommodation'] == "Yes")
{
    $accomodation_val .= 'Participants must deal directly with the hotel. 
                          Please call the hotel direct at +xxxxxx. 
                          Details on accomodation booking are available 
                          <a href="http://abc.com">here</a>.';
}

Note how I changed your echo quote char from " to ' This was to allow for " inside your html string.