This is possible only if you have your post id for which you want to get comments on that particular posts
//Select total no of comments on this post from facebook
$fquery = "SELECT comment_info FROM stream WHERE post_id ='".$idd."'";
$fparam = array('method' => 'fql.query', 'query' => $fquery);
$fql = $facebook->api($fparam);
$cmcount = $fql['0']['comment_info']['comment_count'];
/fetch comments,time,id from facebook on current post
$fquery2 = "SELECT fromid, time,text , id FROM comment WHERE post_id='".$idd."' LIMIT $ofset,$cmcount ";
$fparam2 = array('method' => 'fql.query', 'query' => $fquery2);
$fql2 = $facebook->api($fparam2);
爲什麼downvote downvoter? –