Review the “גמרא דף יב: “איתביה יתר על כן (middle of the Amud) until “אמר רב יהודה”
The Gemara asks a question from the machlokes Rebbe Yehuda and the Rabanan in regards to two mechitzos on the two sides of a Reshus Harabim.
What is the question and the answer of the Gemara?
See Rashi
Questions on Rashi:
How could Rashi say the Rabanan agree to Rebbe Yehuda that only need a lechi or korah on each side? The Gemara on Daf 6a said the rabanan require a tzuras hapesach on one side and a lechi or korah on the other?
If Rebbe Yehuda holds two mechitzos create a Reshus Hayachid where is there a case of a סרטיא or פלטיא that is considered a Reshus Harabim (listed in גמרא שבת דף ו) as their roads had walls on the side of them?
Learn ריטב”א
https://hebrewbooks.org/pdfpager.aspx?req=37287&st=&pgnum=20
Learn תוס’ “איתיביה
Is Tosfos explanation the same as Rashi?
Learn ביאור הלכה ס’ שס”ג, א “אסרו חכמים
https://hebrewbooks.org/pdfpager.aspx?req=60389&st=&pgnum=55
Is Tosfos explanation the same as the Ritva?
Question:
According to the conclusion of the Gemara, how many mechitzas are required to create a Reshus Hayachid?
Learn רא”ש סוכה פרק א ס’ ט
https://hebrewbooks.org/pdfpager.aspx?req=14319&st=&pgnum=469
Learn רמב”ם ה’ שבת פרק י”ז הלכה ט
https://hebrewbooks.org/pdfpager.aspx?req=14278&st=&pgnum=73
Major Question:
The Gemara seems to say clearly that only three walls are necessary to create a Reshus Hayachid. How does the Rambam who rules that four walls are required learn our gemara?
Learn רבינו חננאל on the side of the Gemara for a different way to explain our gemara.
Major Question on ר”ח and Rambam:
In the answer of the Gemara having three walls and a lechi is considered a Reshus Hayachid. But according to Rava לחי is a היכר why is this Mavui considered a Reshus Hayachid?
See דברי יחזקאל ס’ ה אות יב
https://hebrewbooks.org/pdfpager.aspx?req=14038&st=&pgnum=55
https://hebrewbooks.org/pdfpager.aspx?req=14038&st=&pgnum=56