How do we distinguish between the primary narrations, supporting chains, and corroborating narrations in the hadiths of the two Sahihs?

The questioner : How do we distinguish between the primary narrations, supporting chains, and corroborating narrations in the hadiths of the "two Sahihs"?

The Shaykh : How do we distinguish between the primary narrations and the supporting chains?

The questioner : And the corroborating narrations?

The Shaykh : I do not have an answer to this question at hand except by knowing the biographies of the narrators. For example, we know that Muslim does not narrate from Matar al-Warraq in the primary narrations, but only in the supporting chains. Similarly, Sharik ibn 'Abd Allah al-Nakha'i al-Qadi is the same. For example, Muhammad ibn Ishaq ibn Yasar, the author of the Sirah. Following the biographies of the narrators in the "two Sahihs" makes it easier for us to know whether a hadith is in the primary narrations or in the supporting chains and corroborating narrations. This is what comes to my mind now, and peace be upon you.
The student: And upon you peace.