(R. Masna): It is the day on which the dead of Beitar were allowed to be buried.

On that day, they established the Berachah of ha'Tov (that the bodies had not decomposed) ve'ha'Meitiv (that they were allowed to bury them).

(Raba & R. Yosef): It was the day on which they stopped chopping wood for the Mizbe'ach.

(R. Eliezer ha'Gadol): From the fifteenth of Av, the sun's strength wanes, and they stopped cutting wood for the pyre as it wouldn't dry properly.

It was called the axe-breaking day.

From this point on, whoever adds on to his night-time Torah study will have years added to his life.

One who does not do so will be gathered in.

This means that his mother will bury him.

The Mishnah said that the girls would borrow clothing from each other.

A princess would borrow from the Kohen Gadol's daughter, her from the deputy Kohen Gadol's daughter, her from the daugther of the Kohen of war, her from the daughter of another Kohen, and other girls from everyone else, so as not to embarrass whoever did not have.

The Mishnah said that all the garments required Tevilah first; this was true even if they were folded in a closet.

The Mishnah said that they would dance in the vineyards; those who lacked wives would go there.

The beautiful ones would tell them to pay attention to beauty, as a wife is for her beauty.

Those with Yichus would tell them to pay attention to that, as a wife is for her children.

The ugly ones would tell them to marry for the sake of Heaven, and to adorn their wives with golden jewelry.

Hash-m is destined to make a circle of Tzadikim; He will sit inside, and they will point, as the Pasuk refers to them saying "This is my G-d, we will rejoice in His salvation."