[48a - 50 lines; 48b - 25 lines]
1)[line 1]מחייךMECHAYICH- laughs
2)[line 6]המושכיןHA'MOSHCHIN- that flow
3)[line 13]מחיצה תלויהMECHITZAH TELUYAH- a wall which has a gap in the lower part
4)[line 21]"שבו איש תחתיו""SHEVU ISH TACHTAV"- "Every man shall remain in his place" (Shemos 16:29) - "His place" is interpreted as the length of his person.
5)[line 25]מתחת מרגלותיוMI'TACHAS MARGELOSAV- from beneath him (below his feet)
6)[line 35]אי דייקינן כולא האי לא הוי תנינןIY DAIKINAN KULA HAI, LO HAVEI TANEINAN- if we would have been so exacting in our learning (as your question is), we would not have learned anything
7)[line 39]ננס באבריוNANAS B'EIVARAV- a person whose limbs are small in proportion to the rest of his body
8)[line 45]אוושי דיוריןAVSHEI DIYURIN- there are many inhabitants [in the case of three courtyards] (and there is a greater chance that someone may make a mistake and carry between the outer courtyards via the middle courtyard)
(a)THE TORAH LAW - According to Torah law, in a courtyard (Chatzer) which has in it houses owned by different people, all of the neighbors may transfer objects from their houses to the courtyard and into other houses on Shabbos. Even though each house is a separate Reshus ha'Yachid, it is permissible to move objects from one Reshus ha'Yachid to another. Such is also the case when several courtyards open on a dead-end alley (Mavoy - the Rabanan enacted that a Mavoy must have a Lechi or Korah, see Introduction to Maseches Eruvin), or when an entire city is walled (RAMBAM Hilchos Eruvin 1:1).
(b)ERUV AND SHITUF - King Shlomo decreed that transferring objects from a private Reshus ha'Yachid to a public one is forbidden, unless an Eruv Chatzeiros (lit. a mixing of the courtyard, Rambam Hil. Eruvin 1:6; or fraternization of the courtyard, Eruvin 49a) is created on Friday, before Shabbos begins. (Shabbos 14b, Eruvin 21b). (The equivalent of an Eruv Chatzeiros for an alley or a city is called a Shituf Mavo'os.) This is accomplished by all of the neighbors collectively setting aside a loaf of bread, in one common container, in one of the houses of the courtyard (or, in the case of Shituf, in one of the courtyards of the alleyway). This shows that all neighbors have an equal share in all of the Reshuyos ha'Yachid, just as they all have a share in that bread. Through this act, they can be considered one Reshus again. (An Eruv Chatzeros uses bread. A Shituf is not limited to bread; any food may be used except for water, salt and mushrooms.) (RAMBAM ibid. 1:4-9)
10)[line 2]שגבו את עירובןSHE'GAVU ES ERUVAN- that collected [the food for] their Eruv Chatzeiros
11)[line 22]רשות אחת משמשת לשתי רשויותRESHUS ACHAS MESHAMESHES LI'SHTEI RESHUYOS- One courtyard may be subordinate to and used by two adjacent courtyards