JSFiddle - React, Tailwind, and code Playground

HTML

<script src="http://ajax.microsoft.com/ajax/jquery.validate/1.7/jquery.validate.js"></script>
<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.2/themes/ui-lightness/jquery-ui.css">
<div id='id'></div>

JavaScript

var querystr = 'ca';
var result = "Calculator";
var reg = new RegExp(querystr, 'gi');
var final_str = 'foo ' + result.replace(reg, function(str) {return '<b>'+str+'</b>'});
$('#id').html(final_str);