Putting an image next to “add a comment”

I’m trying to add a little image/button next to the text/link “add a comment”. I’m not sure the php on how to do it, and whenever I add <img> in the code I get a parse error. Can anyone help?

I’m sure everyone knows what this look like. Where do I put in the image location? ———->

<?php if( !is_single() ) {

echo “, “;
// comments are open so display a link to them
if ( comments_open() ) {
comments_popup_link( “add a comment”, “1 comment so far”, “% comments”, “comments”

);

// otherwise comments are closed
} else {
?> ” class=”comments”>comments closed