The present perfect continuous is constructed by prefixing می particle to the present perfect (note that the construction of the past perfect continuous is dependent upon the past participle):

This tense is used in reference to an action or state which was continuous or habitual in the past, while the narrator never witnessed it personally. For instance, such a sentences as, ما ایرانی ها در گذشته این کار را می کرده ایم mā iraniha dar gozašte in kārde-im ‘We Persians used to do this in the old days,’ indicates that the narrator did not exist in those (ancient) days, when Persians “used to do this.” He uses the first plural pronoun only to indicate that he too is Persian—nothing more.

Pay attention to, and analyze, the following sentence:

این مرد لباس های کهنه را می خریده است و به تنگدستان می داده است
in mard lebāshay-e kohne rā mixaride ast va be tangdastan midade ast
“This man used to buy used clothes and give them to the needy.”

In this sentence the fact that the narrator was not personally present to witness the event is expressed through this particular construction of the sentence.

In addition, a sentence like this is usually preceded by such declarations as: “I have been told,” “they say,” “apparently,” “it has been said to me,” “there are those who can testify,” or “rumor has it.” A clause like this may or may not be linked to the sentence by means of the که conjunction:

می گویند که این مردمان از شمال می آمده اند و کالاهای ما را می خریده اند/می گویند این مردمان از شمال می آمده اند و کالاهای ما را می خریده اند

miguyand in mardoman az šomāl miāmade-and va kālāhay-e mā rā mixaride-and
miguyand ke in mardoman az šomāl miāmade-and va kālāhay-e mā rā mixaride-and
“They say that these people used to come from the North and buy our merchandise.”