<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<p>Phasellus sit amet auctor velit, ac egestas augue.</p>
<script>
jQuery(document).ready(function($){  
		
	$('p').html(function(){	
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		// to the last word
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	});

});
</script>
<style>
span{
color:red;
}
</style>