????:1?????????:?????100????

2?????

3???????????

4??????????

5???????????

1?1??8???21????????,??C919????MU721“?????”???????????,???157?????????,??????????????

???7???,????“??????”??,????????C919“?”???,???“??”????????????????????????,?????

????????????????????,?????C919“????????”????????1????,???????MU721/MU722?

(???? ??? ?????????????? ?????????) ???:????????????????????????????