Explanation #1 (Rashi): It has two walls along the length, like a Mavuy Mefulash (open on two opposite ends).

Rejection: In Sukah (18b), Abaye answers Rava "I agree with you about this, for it is like a Mavuy Mefulash, and we do not say Pi Tikra Yored v'Sosem"!

Explanation #2: Rather, [it has two adjacent walls;] it is like [the Greek letter] Gamma (like an "L" shape). It is not proper to elaborate.

Explanation: [One may sow on the other side] due to Pi Tikra.

Implied question: Regarding Shabbos, Shmuel holds that we say Pi Tikra only when there are four Mechitzos, according to the text of R. Chananel and R. Tam (94b)!

Answer: Even so, we can distinguish between Kil'ayim and Shabbos, like it connotes above (11a).

Implied question: Why do we say above (92a-b) that the small is like an opening of the big, even for Kil'ayim? (Perhaps Kil'ayim is different!)

Answer: The extra words in our Mishnah "because it is like an opening of the big" connotes that for everything, it is like its opening.

Implied question: This should be like nine in the small and an individual in the big! (We do not consider those in the big to be in the small.)

Answer: Here there is a reason, like it says "for [the one in the middle] goes out to here and to here."

Explanation #1 (Rashi in Gitin 15b): E.g. there is a furrow five [Tefachim] deep and it has walls five [tall]. They do not join to make inside a Reshus ha'Yachid.

Question (R. Tam): It says below (99b) that a pit and its Chulya (the earth dug out of it and piled up next to it) join!

Also in our Sugya, it says that Rav Chisda agrees about the bottom, since it sees [a wall] 10!

Explanation #2: "Gidud Chamishah" is a height of five. It is relevant to two Chatzeros, one above the other, and the top one (if it has a wall five), like it says here.

Question: This requires investigation regarding Shabbos, if there is a mound in Reshus ha'Rabim five tall and four wide, and on it they made a Mechitzah five. One who throws from Reshus ha'Rabim into it is liable, and from it to Reshus ha'Rabim is exempt.

Implied question: Above, when [the Makshan] asked that the top should not be Me'arev, not one (together with the bottom) and not two (individually), why don't we answer that (indeed, this is true); [Rav Chisda] taught "may be Me'arev two, but not one", regarding the bottom!

Answer: It connotes to [the Makshan] that "may be Me'arev two" applies to both of them.

Question: Here Abaye says that Rabah holds like Shmuel, who says that since Shabbos was permitted, it was permitted;

If so it is difficult, for Abaye himself (22a) said that [Rabah] followed all Rav's stringencies, except for three matters that he did like Shmuel - one may remove [Tzitzis] from a garment to [put them on] another garment...

Suggestion: [There] it does not count the law here, because also Rav Huna and Rav Yehudah hold like Shmuel.

Rejection: Regarding dragging [a bench on an earth floor, without intent to make a furrow, which is listed among the three,] others hold like Shmuel, for in Shabbos (81a) it connotes that R. Yochanan holds like the Stam Mishnah, that a Nazir may shampoo and separate his hairs (even though he might detach hairs, because it is Davar she'Eino Miskaven)!

Answer #1 (and defense of suggestion): We can say that in Shabbos, [the Gemara] asks as follows. Can R. Yochanan say that Davar she'Eino Miskaven is forbidden, unlike a Stam Mishnah of Nazir?

Even if there is another Stam Mishnah [that forbids], like we find in Beitzah (23b), why is that Stam stronger than this one? R. Yochanan should not rule like any one of them without a proof.

Answer #2: [Rabah] followed Rav's stringencies, i.e. in general, except for Eruv and Aveilus, for in them, the Halachah follows the lenient opinion.

Answer #3: Since sometimes this leniency is a stringency, e.g. he was forbidden for part of Shabbos - for this reason, he is forbidden for all of Shabbos - [Abaye] does not count them among stringencies of Rav;

[This is because just like] Rav does not hold that since it was permitted, it was permitted, he does not hold that since it was forbidden, it was forbidden.

Reference: I explained this above (17a. The Halachah follows Rav Huna, that once Shabbos was permitted, it is permitted, e.g. there was a change of residents. However, when there are no walls, the Heter ceases, like R. Yosi.)

Explanation: This refers to Kelim that were Shoves in the house, according to R. Shimon.

Explanation: The Gemara establishes this in the place of the breached wall, and when nothing at all remains from the two walls on its side, that the place of this Mechitzah that was breached is not inside the remaining walls.

In the first version it establishes it when a path was lost in that place, and [the public] chose the place of the walls to be their path to walk there, in place of their path that was lost there;

R. Eliezer holds like he taught [elsewhere]. He holds that what they chose, they chose (they keep it). Rabanan hold that they have no power to choose. Therefore, even though they pass there, it is not Reshus ha'Rabim, since it was not handed over to the Rabim and it does not belong to the Rabim, like we said above (22b) "do you discuss paths of Beis Gilgul?!" (They were very steep, and inconvenient to use, so Yehoshua did not give them to the Rabim, so they are not Reshus ha'Rabim.)

Implied question: Why did R. Eliezer say "mi'Tochah"? (He does not discuss from its interior!)

Answer: "Mi'Tochah" is not precise. Rather, because Rabanan said mi'Tochah, also he said mi'Tochah, like it says in the Gemara;

Rabanan answer him as follows. Don't you agree that if he was Motzi from inside to Reshus ha'Rabim, he is exempt, but it is forbidden, because the Rabim have no rights there, therefore it does not become Reshus ha'Rabim, even if all the walls around it fell, and it is Karmelis;

Also here, the place of the wall, admit that it is Karmelis, for they have no rights in their choice!

Implied question: Why did Rabanan abandon Reshus ha'Yachid, like R. Eliezer said, and they mentioned Reshus ha'Rabim?

Answer #1: It is because R. Eliezer discussed the place of the wall, that it is Reshus ha'Rabim, and said that if he was Motzi from inside the Chatzer, which is Reshus ha'Yachid, to the place of the wall, he is liable;

However, Rabanan, who discuss when he was Motzi or entered into the actual interior, and even when all the Mechitzos fell, mentioned Reshus ha'Rabim next to [the Chatzer] that is mentioned in the Mishnah;

They did not want to teach that if he was Motzi from it (the interior) to a Chatzer next to [the Chatzer whose walls fell, that he is exempt, for the fallen Chatzer is not Reshus ha'Rabim] because our Mishnah did not mention that there was [another] Chatzer next to it.

Answer #2: They mentioned Reshus ha'Rabim to prove that the interior is very different from Reshus ha'Rabim;

If it were not very different [from Reshus ha'Rabim], it would be permitted to bring from Reshus ha'Rabim into it.

Implied question: Teaching that one who is Motzi from Reshus ha'Yachid to it is exempt shows that it is very different [from Reshus ha'Rabim]!

Answer: [No, for] even if it were only slightly different from Reshus ha'Rabim, one who was Motzi from Reshus ha'Yachid to it would be exempt, since it is not truly Reshus ha'Rabim.