<html>
<head>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.1.1/jquery.min.js" type="text/javascript"></script>
</head>
<body>
<div class="lead">
<ul>
</ul>
</div>
<script>
var arr = [['1'],['2'],['3']];
arr.forEach(function(ar){
$('.lead ul').append('<li><p>'+ar[0]+'</p></li>');
});
</script>
</body>
</html>