If he comes back,please let me know.

please let me know if he comes 中的if不可用whether代替 状语从句,主将从现原则：If he comes back,please let me know.如果他回来,请通知我,主 IF HE ____?[COME]BACK,PLEASE LET ME KNOW怎么写? If Mr Green__ back, please let me know（come) please let me know if he ------------(come) tomorrow? Do you know if ____back next week?If he ___ back,please let I don't know if he_.if he _home,please let me know.(return). I wonder if he _____.if he ______,please let me know as soon If he comes ,please let me know_____ _____ _____ _____(尽快) If Mrs.Green ______(get)back,please let me know.填空 If Mr Smith___back,please let me know. If you know when he will come,please let me know.(改写同义句)