<!DOCTYPE html>
<html>
<head>
<script src="https://libs.baidu.com/jquery/2.1.4/jquery.min.js"></script>
<script>
function changeSize() { $(this).animate({fontSize: "+=10px"});}
function changeSpacing() { $(this).animate({letterSpacing: "+=5px"});}
$(document).ready(function(){ $("p").on("click", changeSize); $("p").on("click", changeSpacing); $("button").click(function(){ $("p").off("click", changeSize); });
});
</script>
</head>
<body>
<p>This is a paragraph.</p>
<p>This is another paragraph.</p>
<p>Click any p element to increase size and letterspacing.</p>
<button>Remove the changeSize() event handler</button>
</body>
</html>