<?php the_category(); ?>

<ul>
	<?php
		$args = array(
		'post_type' => 'post',
		'posts_per_page' => 9,
	); ?>
	<?php $wp_query = new WP_Query( $args ); ?>
	<?php while ( $wp_query->have_posts() ) : $wp_query->the_post(); ?>
	<li>
		<?php the_category(); ?>
		<h2>タイトルが入ります</h2>
		<p>本文が入ります。</p>
		<!--以下省略-->
	</li>
	<?php endwhile; ?>
	<?php wp_reset_postdata(); ?>
</ul>

<?php $cat = get_the_category(); $cat = $cat[0]; { echo $cat->cat_name; } ?>

<?php 
	$cat = get_the_category();
	$cat = $cat[0];
	?>
<div class="<?php echo $cat->category_nicename; ?>"><?php the_category(' '); ?></div>

<div class="event"><a href="#">イベント情報</a></div>

<?php $cat = get_the_category(); $cat = $cat[0]; {
  echo '<div class="'. $cat->category_nicename .'">'; 
 } ?>
<?php $cat = get_the_category(); $cat = $cat[0]; { echo $cat->cat_name; } ?></div>

<div class="event">イベント情報</div>