async-await实现同步

function delay(word){
 return new Promise((resolve,rejected)=>{
    setTimeout(() => {
      resolve(word)
    }, 2000);
  })
}
// async+await一起使用
async function start(){
  const word1 = await delay('1')
  console.log(word1)
  const word2 = await delay('2')
  console.log(word2)
  const word3 = await delay('3')
  console.log(word3)
}
start()