Second: This occurs when a narrator possesses only a portion of the text; he holds that portion (1) through a different isnād. A later transmitter then relates the entire report from him but cites the first isnād. A similar situation is when the narrator hears from his shaykh only part of the ḥadith (2), then hears the remainder (3) from the same shaykh through an intermediary (4); someone later transmits the full ḥadith from him (5) while omitting the intermediary (6).
Third: A narrator may have two different texts (7), each with its own isnād. A subsequent transmitter reports both texts from him while mentioning only one (8) of the two isnāds, or he relates one of the two reports with its particular chain but inserts into it material from the other text that was not present in (9) the first.
Fourth: A narrator may begin citing an isnād (10), when something interrupts him, prompting him to insert words of his own (11). Some of the listeners (12) assume that these words are the matn of that isnād and transmit it from him accordingly.
These (13) are the divisions of interpolated isnād (14).