[87a - 24 lines; 87b - 18 lines]
1)[line 1]קרעיםKERA'IM- rents that are made in garments, for mourning
2)[line 1]"ויחזק דוד בבגדו ויקרעם וגם כל האנשים אשר אתו. ויספדו ויבכו ויצמו עד הערב על שאול ועליהונתן בנו ועל עם ה' ועל בית ישראל כי נפלו בחרב""VA'YACHAZEK DAVID B'VEGADAV VA'YIKRA'EM, V'GAM KOL HA'AM ASHER ITO. VA'YISPEDU, VA'YIVKU, VA'YATZUMU AD HA'EREV, AL SHAUL V'AL YEHONASAN V'AL BEIS YISRAEL KI NAFLU BE'CHAREV" - "And David took hold of his clothes and tore them, and so did the men who were with him. And they eulogized, they wept, and they fasted until the evening for Shaul, for Yehonasan, and for the house of Yisrael, who fell by the sword." (Shmuel II 1:11-12) (MOURNING THE DEATH OF SHAUL AND YONASAN)
See Background to Moed Katan 26:7.
3)[line 17]בתוך כדי דבורB'SOCH KEDEI DIBUR
"Toch Kedei Dibur" is the length of time that it takes for a student to say a greeting to his teacher (e.g. "Shalom Aleicha Rebbi"). "K'Dibur Dami" means that within this small amount of time, we view an act or speech as not yet completed and still continuing. Thus, even though the person has, with regard to his actions, already stopped performing the act, within this amount of time he may act or say something that will abrogate his previous actions or words. For example, if a person sells an object and changes his mind within Toch Kedei Dibur, the sale is nullified.
4)[line 19]ממגדףMEGADEF
The Torah states that a Megadef is punishable with Kares (Bamidbar 15:30). There are two opinions regarding the definition of the Megadef in that verse: (a) a person who curses HaSh-m; (b) a person who plays music and sings to Avodah Zarah. However, the Megadef in our Gemara is clearly the former, since playing music to Avodah Zarah is prohibited along with worshipping Avodah Zarah, which is already mentioned in the Gemara.