SOURCE

const sleep = (wait)=>{
     return new Promise((resolve)=>{
         setTimeout(resolve,wait)
     })
 }
 
 (async()=>{
     for(let i =0;i<6;i++){
         if(i<5){
             console.log(new Date(),i);
             await sleep(1000)
         }else{
             await sleep(4000)
             console.log(new Date(),i);
         }
     } 
 })()