使用微信开发者工具JS编译中else if条件不成立为什么依旧会进去

Question

微信开发者工具JS编译中else if条件不成立为什么依旧会进去

let Unit
let CY =parseInt(bigNum.add(Cycleunit[0],-3),16)
 //此时CY为9
let Cycleunit3

  if(CY<4){
    Unit ="分"
    let Cycleunit1 = Cycleunit.join("")
    let Cycleunit2 = bigNum.add(Cycleunit1,-33)
    Cycleunit3 = parseInt(Cycleunit2,16)
  }
  else if(4<=CY<=7){
    Unit ="时"
    let Cycleunit1 = Cycleunit.join("")
    let Cycleunit2 = bigNum.add(Cycleunit1,-73)
    Cycleunit3 = parseInt(Cycleunit2,16)
  }
  else if(8<=CY<=11){
      Unit ="日"
      let Cycleunit1 = Cycleunit.join("")
      let Cycleunit2 = bigNum.add(Cycleunit1,-"b3")
      Cycleunit3 = parseInt(Cycleunit2,16)
    }

Answer 1

else if(4<=CY<=7){ 不能这样写
else if(CY>=4 && CY<=7){