Introducing divorce. Including how the verses on divorce in the Torah provide the details of halakhic divorce, most saliently that a man gives a woman a divorce, and the reverse is not acceptable. Also, the first mishnah, and its description of how one can use an agent or emissary (shaliach) to convey a get (bill of divorce) and it will be an effective divorce. With geographical details that define the land of Israel, and certain requirements for witnesses.