如何利用Javascript在标签内外插入标签元素

li= document.createElement("li");

 li.textContent="第一个元素";

ul.insertAdjacentElement("afterbegin",li);

 li= document.createElement("li");

 li.textContent="最后一个元素";

 ul.insertAdjacentElement("beforeend",li);

a=document.createElement("a");

a.innerText="《雪中悍刀行》";

a.href="http://www.baidu.com";

ul.insertAdjacentElement("beforebegin",a);

a1=document.createElement("a");

a1.innerText="《剑来》";

a1.href="https://www.php.cn/";

ul.insertAdjacentElement("afterend",a1);