1)

(a)Rebbi Yehudah and Rebbi Meir argue about transforming a cabin with an uncemented roof comprising four-Tefachim planks into a Sukah. According to Rebbi Yehudah, Beis Shamai require two acts for the Sukah to be Kasher - 1. shaking the planks; 2. removing every second one and re-placing it with Kasher Sechach.

(b)Beis Hillel permit either of the two.

(c)Rebbi Meir says - that one remove every second plank.

(d)Rav and Shmuel, who argued over the Machlokes between Rebbi Meir and Rebbi Yehudah on the previous Daf, interpret the Machlokes differently. According to Rav - R. Yehudah is not concerned about Gezeiras Tikrah, which explains why he has a choice of shaking all the planks, should he prefer; Rebbi Meir is (which is why he has no choice).

2)

(a)We conclude - that Beis Shamai are concerned about Gezeiras Tikrah, and that when, according to Rebbi Yehudah, they say 'Mefakfek v'Notel Achas mi'Beineihem', what they really mean is that even if if he shakes the planks, he remains obligated to remain every second one.

(b)We reconcile this with Rebbi Meir, who says the same thing, not because he holds like Beis Shamai, but - because, in his opinion, Beis Shamai and Beis Hillel both agree to it.

(c)The basis of the Machlokes between Rebbi Meir and the Rabanan is - whether we hold of Gezeiras Tikra (Rebbi Meir) or not (Rebbi Yehudah).

(d)The problem with this is - that this is a duplication of their Machlokes in the previous Mishnah.

3)

(a)To solve the problem, how Rebbi Chiya bar Aba Amar Rebbi Yochanan tries to establish the earlier Mishnah by 'sharpened planks' - which are Kelim (that are generally Kasher since flat wooden vessels are not subject to Tum'ah), but which R. Meir declares Pasul on account of Kelim which are subject to Tum'ah ...

(b)... whereas R. Yehudah declares Kasher (because he does not hold of the decree).

(c)We refute this explanation however, on the basis of a statement by Rav Yehudah Amar Rav, who rules that 'male arrows' (that do have a receptacle) are Kasher for Sechach (and we do not forbid them because of female arrows.

(d)So we establish both Mishnahs by Gezeiras Tikrah. And as for the original question, why we need two Mishnahs to teach us the same thing - we answer with the need of R. Yehudah and R. Meir to teach us their opinions regarding Beis Shamai and Beis Hillel, whether they argue over Gezeiras Tikrah (Rebbi Yehudah) or not (Rebbi Meir).

4)

(a)This is fine according to Rav. The problem according to Shmuel (considering that Rebbi Meir and Rebbi Yehudah are arguing over planks that are four Tefachim wide) is - what is the basis of their Machlokes in the Seifa? On what grounds does Rebbi Yehudah according to Beis Hillel permit Pikpuk (and leaving the planks intact)?

(b)The answer is that according to Shmuel - Rebbi Yehudah permits even planks of four Tefachim, provided one does something to be Mevatel their status as part of a ceiling (since then the suspicion that one may come to use a ceiling no longer exists) and it is to that end that Beis Hillel permits even four-Tefach planks in our Mishnah by merely shaking them. R. Meir disagrees.

5)

(a)Our Mishnah permits using metal rods or bed-posts (that are subject to Tum'ah) - provided one leaves the equivalent space between them as the slats themselves.

(b)The Tana - forbids scratching a Sukah out of a hay-stack ...

(c)... because it constitutes 'Ta'aseh v'Lo min he'Asuy'.

6)

(a)Rav Papa and Rav Huna brei d'Rav Yehoshua argue over 'Parutz k'Omed' - (in connection with the walls of a Reshus ha'Yachid on Shabbos).

(b)Rav Papa holds 'Parutz k'Omed Mutar' - meaning that if the spaces between the posts that form a wall were exactly the same as the posts themselves, the wall is Kasher. (Note, that this does not apply to spaces of less than three Tefachim, where we apply the principle of 'Lavud').

(c)Rav Huna brei d'Rav Yehoshua - holds 'Parutz k'Omed, Asur'.

7)

(a)Our Mishnah poses a Kashya on Rav Huna brei d'Rav Yehoshu'a - since the words 'Im Yesh Revach Beinehen Kamosan' implies that Parutz k'Omed is Kasher.

(b)To answer the Kashya, the latter explains 'Kamosan' in our Mishnah to mean - that there is sufficient space for the Sechach to fit in the space (which entails it being a fraction wider than the rods or the posts).

(c)We query this answer however with the Kashya 've'Ha Efshar Letzamtzem' - meaning that it is possible to leave exactly the same amount space without the extra fraction if one makes the effort.

8)

(a)Rav Ami answers 'be'Ma'adif' - by which he means that our Mishnah nevertheless speaks when one deliberately left the gap slightly wider than the rods to enable the Sechach to fit in with ease.

(b)Rava answers - that the Mishnah can even speak where the gaps are exactly the same width as the rods, only, according to Rav Huna brei d'Rav Yehoshua, it speaks where one spreads the Sechach across the top of the rods, not parallel to them. By doing so, he cannot avoid placing more Sechach than rods, because, otherwise, it would fall through the gaps.

9)

(a)Rav Ami bar Tivyumi invalidates a Sukah if the Sechach comprises worn out vessels or clothes that are no longer fit for use (despite the fact that they are no longer subject to Tum'ah) - in case one comes to use them before they become unfit for use.

(b)His opinion cannot be borne out from our Mishnah, which invalidates a Sukah whose Sechach comprises bed-posts - because our Mishnah may be speaking in a case when the bed-posts (either length-wise or width-wise) are placed on the Sukah, together with the two legs still attached to them, and such bedposts are still fit for use (and therefore subject to Tum'ah, as Rebbi Chanin Amar Rebbi explains elsewhere).

10)

(a)Rebbi Chanan Amar Rebbi is actually referring to a Mishnah in Kelim, where Rebbi Eliezer declares Tamei a bed 'Chavilah' - meaning only when it is complete (but not when it is in pieces.

(b)The latter then adds - that it can also only be Toveled when it is complete (but not piece by piece).

(c)The Chachamim rule - that it can become Tamei when it is in pieces and it can be Toveled in the same way.