这很容易。

//Include this above your loop
$i = 0; //Counter

if(have_posts())while(have_posts())the_post();

    //include this in your loop
    $i++;
    if($i <= 5)
        echo "<img src=\'http://urltoinewimage\' alt=\'Image Title\' />";
    //Stop including in your loop

    the_title();
    the_content();
endwhile; else:
endif;