Untitled

<!DOCTYPE html>
   <body>
   <p id="event_01">Click</p>

   <script>
   let goo = document.querySelector("#event_01");

   let clickOnce = function() {goo.innerHTML = "Clicked"};

   let clickBack = function(){
   goo.innerHTML = "Click"};

   if(goo.textContent == "Click")
   {goo.addEventListener("click", clickOnce);}
   elseif (goo.textContent == "Clicked"){
   goo.addEventListener("click", clickBack);}

   </script>

   </body>