pengertian , contoh dan rumus pas future perfect continuous tense

kalo pengertiannya kurang tau, guna nya kurang tau juga
karena penggunaan tense ini jarang yg sering di pake itu cuma 14
rumus nya
S + will have been + present participle(Ving)

contoh:
you will have been waiting for more thow hours when her plane finally arrive

atau bisa juga dengan "be going to"
pattern : S+is/am/are going to have been+present participle

contoh:
you are going to have been waiting for more thow hours when her plane finally arrive