Cómo mostrar imagen destacada en contenido de forma visible

<?php if( has_post_thumbnail() ) : ?>

<?php get_header(); ?>
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<div id="blocks-wrapper" class="clearfix">
<?php if ( function_exists('yoast_breadcrumb') ) { yoast_breadcrumb('<p id="breadcrumbs">','</p>'); } ?>
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	<!-- /blocks Left -or -right -->
	<div id="blocks-left" <?php post_class('eleven columns');?>>	 		
		
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			  if($data['posts_bread'] == 'On' ) {
			  imagmag_themepacific_breadcrumb(); 
			  }
			 ?>						
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 				  <div class="post-title"><h1 class="entry-title"><?php the_title(); ?></h1></div>
				  <!--/.post-title-->
 		<!--/#post-meta --> 
			<div class="post-meta-blog">
			<span class="meta_author"><?php _e('Posted by', 'imagmag'); ?> <?php the_author_posts_link(); ?></span>
			<span class="meta_date"><?php _e('On', 'imagmag'); ?> <?php the_time('F d, Y'); ?></span>
			<span class="meta_comments"><?php _e('', 'imagmag'); ?>  <a href="<?php comments_link(); ?>"><?php comments_number('0 Comment', '1 Comment', '% Comments'); ?></a></span>
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			<!--/#post-meta --> 
			 <!-- .post_content -->

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			<?php endif; ?>



			<div class="comparte">
			    <aside id="compartir2"></aside> 
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					<?php dynamic_sidebar( 'inicio-post' ); ?>
			<?php endif; ?>



			  <div class = 'post_content entry-content'>
  					<?php the_content(); ?>
  					<div class="clear"></div>
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				<section class="publicidad-abajo-titulo">
					<?php dynamic_sidebar( 'pub-abajo' ); ?>
				</section>
			<?php endif; ?>

			
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						<strong>TOPICS </strong><?php the_tags('',''); ?>					
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			<?php } ?>
 
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 				<?php endwhile; endif; ?>
			
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<?php get_footer(); ?>

<div class = 'post_content entry-content'>
  					<?php the_content(); ?>
  					<div class="clear"></div>
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<?php
if ( has_post_thumbnail() ) { // check if the post has a Post Thumbnail assigned to it.
  the_post_thumbnail();
}
?>

<?php the_content(); ?>