怎样操作JS动态添加标签与删除标签

<p>
 </p><p>1</p> <button>添加</button>

function myFun9() {
 var mp3 = document.getElementById("mp3"); //获取组件1
 var eleme = document.createElement("p"); //创建组件2
 var ele_content = document.createTextNode("2");//创建节点内容
 eleme.appendChild(ele_content); // 组件添加节点
 mp3.appendChild(eleme); //组件2加入组件1
 }
==================删除==============================
<button>删除</button>
 <p>
 </p><p>1</p>
 <p>2</p>
 <p>3</p>
 <p>4</p>
 <p>5</p>
 
function myFun10(){
 var parent=document.getElementById("mp4");
 var son=document.getElementById("p1");
 parent.removeChild(son);
 }

nbsp;html>


 <meta>
 <title>Document</title>
 <style>
  body,ul{
   padding: 0;
   margin: 0;
  }
  ul{
   list-style: none;
  }
  .lunbo{
   width: 730px;
   height: 454px;
   margin: 100px auto;
   overflow: hidden;
   position: relative;
  }
  .circle{
   position: absolute;
   left: 50%;
   margin-left: -50px;
   bottom: 10px;   
  }
  .circle span{
   display: inline-block;
   width: 18px;
   height: 18px;
   background-color: #ccc;
   text-align: center;
   border-radius: 18px;
   cursor: pointer;
   margin-right:10px;
  }
  .circle span.current{
   background-color: yellow;
  }
 </style>
 <script> 
  window.onload = function(){
   function $(id){ return document.getElementById(id); }
   //动态生成轮播图小圆点
   var circle = document.createElement("p"); 
   circle.setAttribute("class","circle");
   var lis = document.getElementsByTagName("li");
   for(var i=0; i<lis.length; i++){
    var span = document.createElement("span");
    span.innerHTML = i+1;
    circle.appendChild(span);
   }
   $("scroll").appendChild(circle);
   var spanChildren = circle.children;
   spanChildren[0].setAttribute("class","current");
  }
 </script>
 <p>
  </p>