How to show post by category in wordpress | wordpress.

query_posts( array( 'category_name' => 'news', 'posts_per_page' => 3) );

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

 the_permalink();

the_time('d M');

if ( has_post_thumbnail() )
{


 the_post_thumbnail('full');



 }


echo the_title();



echo substr(get_the_content(), 0,250)


 endwhile; endif; wp_reset_query();