<div>
    <p>Something_1</p>
    <p>Something_2</p>
    <p>Something_3</p>
    </div>
    <script>
        $('p').first().css('color','blue');
    $('p').slice(1,3).css('color','red');
    $('p').slice(-2).css('color','green');
    $('p').closest("div").children().last().css('color','red');
</script>