Perfect continuous tenses implies the following things;
It means the situation shows both continuity and completion of verbal action and that is why it is called perfect continuous tense.
It is owing to the two situations in a sentence that there are two auxiliary verbs used together which is explained below.
Thus the sentences will be like;
In perfect tenses we have observed that past participle form is always used after have, has or had and it is because of this that we have to use been which is past participle form of be, like; have been, has been, had been.
For future perfect continuous we have to use shall or will as mentioned in previous chapters. Shall is used with first person pronouns whereas for others subjects we shall use will. For more details regarding the uses of shall and will you better go to the chapter of simple tenses.
Since in this tense we have to show continuity of verbal action for certain time hence we have to use present participle (–ing) form of the main verb.
Use of auxiliaries in present, past and future perfect continuous tenses
If you look at the names of verbs you will see that first from is called present and second is past. It is by here that we get to know which form of auxiliaries are used in present and past perfect continuous tenses. Use first form of auxiliary verb in present perfect continuous and second form of auxiliary verb in past perfect continuous as defined below.
As it is explained already in previous chapters that verb in English language doesn’t stand for future hence we have to use modal operators (shall and will) for future perfect continuous tense.
More details of auxiliaries
Has been is used with the subjects like; he, she, it and singular noun in present time situation. Have been is used with the subjects like; I, we, you, they and plural noun in present time situation. Had been is used with all subjects in past time situation. Shall have been is used with first person pronouns (I and we). Will have been is used with second person pronoun (you), third person pronoun (he, she, it, they) and singular and plural nouns as subject. Note: Remember whenever you are showing stress on the verbal action in future time situation you have to exchange will and shall. Use will in the place of shall and shall in the place of will.
The use of since
is associated with perfect continuous tenses. They are treated
in another chapter and for the details you must go to Since
and for lesson.