ShortcodeTwo Columns

Hello,
How can I insert a Shortcode in the page to have two columns?
My code does not work, the second column goes under the first because of <p> that is in the article. Can you help?

thanks a lot

<?php echo "<div class='one_half'>"; ?> <?php the_content(__('read more',  "site5framework")); ?> <?php echo "</div> <div class='one_half last'> Column 2 </div><div class='clearboth'></div>"; ?>