1)

(a)The Tana of one Beraisa permits handling a Shofar on Shabbos, but not a trumpet - because a trumpet is straight, and is not fit for any other use. Consequently, it is purely a 'K'li she'Melachto le'Isur', which is Muktzah; whereas a Shofar, which has a curved shape, is fit to be used as a receptacle (for a child to drink wine from), and is therefore not Muktzah (according to Rebbi Yehudah, as we shall see shortly).

(b)We initially reconcile this Beraisa with another Beraisa that forbids even the handling of a Shofar - by establishing the former, by a communal one, which is not used for drinking - and the latter, by a private one.

(c)This answer is not acceptable however - because a communal Shofar too, is not only fit to be used for the same purpose, but was also used to give a poor child to drink (in view of the duty of the community to feed the poor).

(d)The Gemara ultimately answers that the author of the Beraisa that forbids even a Shofar is Rebbi Nechemya - who holds that one may only move an object for the main purpose for which it was designated. Consequently, a Shofar, which is designated for blowing (and not for drinking), will be Muktzah.

2)

(a)The author of the Beraisa that permits handling even a trumpet - is Rebbi Shimon, who does not, as a rule, hold of Muktzah.

(b)The problem with the Beraisa that forbids both the Shofar and the trumpet (in that order) is - that since Rebbi Nechemya forbids the handling of a Shofar, as well as a trumpet, why did he need to mention a trumpet at all, after telling us that a Shofar is Asur? Is it not then obvious, that a trumpet will be Asur too?

(c)We deal with this problem - by explaining the Shofar that he mentioned to mean, ot a Shofar, but a trumpet (and vice-versa). In fact, this Beraisa was learnt in a place where they had already adopted the custom to switch the two names. Now we can say that the Tana prohibits the handling of a trumpet, and even of a Shofar ('Lo Zu, Af Zu' - mentioning the less obvious first, as is customary among Tana'im).

(d)The ramifications of the switch between a Shofar and a trumpet is - that after the switch, one would only be Yotze if he heard the blowing of a 'trumpet', but not of a 'Shofar' (so if a Ba'al Tokei'a said that he had blown a Shofar, one would not be Yotzei). Alternatively, if an Am ha'Aretz asked what to blow, we would have to tell him to blow a 'trumpet'.

3)

(a)Together with the Shofar and trumpet - Rav Chisda also lists the names of an 'Aravah' (a willow that is Kasher for Succos, and a 'Tzaftzefah' (one that is not, because it has a round leaf and a white stem), and those of a 'Pesorah' (the original name for a large table) and a 'Pesorta' (the name for a small table).

(b)The ramifications of the switch between a 'P'sorah and a 'P'sorta' - concerns a business deal in which someone agrees to sell his friend a Pesora or a Pesorta, who would be obligated to provide the purchaser with what it is called now, and not with what it was originally called.

(c)Abaye adds the Huvlila (the Meses) and the Bei Kasi (the Beis ha'Kosos in an animal's stomach). The Meses is surrounded by a thin layer of skin, and is therefore T'reifah if a needle pierces the skin. But the Beis ha'Kosos is surrounded by a double layer of skin, with the result that, should a needle pierce it, it is only T'reifah if it pierced both layers, but not if it pierced only one. If someone should now ask a Rav about a needle which pierced a 'Huvlila', he would be referring (not to the Meses, as would formerly have been the case, but) to the Beis ha'Kosos, in which case the animal might now be Kasher. Whereas if he asked him about a needle which pierced a 'Bei Kasi', the Rav would be forced to pronounce the animal T'reifah at all costs.

(d)And the ramifications of the switch between Bavel and Bursif - concerns the area of Gitin, where a Get which a Sh'liach brings from Bavel was Kasher without his needing to say 'be'Fanai Nichtav u'be'Fanai Nechtam') - because the Sofrim in Bavel were experts in writing Gitin li'Sh'mah (with the correct intentions), whilst in Bursif, they were not (and the Sh'li'ach who brought the Get had therefore to declare 'be'Fanai Nichtav' etc.). After the switch, it was the Sh'li'ach from Bursif who did not need to say 'Be'Fanai Nichtav' etc., and the Sh'li'ach from Bavel who did.

4)

(a)A Kirah is an oblong-shaped oven which has space for two pots inside it.(Most of our ovens have the Din of a Kirah.)

(b)The Mishnah permits one to leave things to cook on a Kirah from Erev Shabbos to Shabbos - when it has been lit with straw or stubble.

(c)It is permitted to leave a pot on a Kirah which was lit with Gefes (pressed sunflower seeds) or with wood, provided one first cleared out the coals or made 'Ketimah' - the placing of ashes on top of the burning coals, indicating that one does not want them to cool down (and is therefore not interested in stoking them).

(d)Beis Hillel permit the placing, not only of hot water on to a Kirah which is Gerufah and Ketumah, but also other cooked foods, as well as returning them on to the stove. Beis Shamai forbid - leaving other foods on the stove, because, in spite of the fact that it is 'Gerufah' or 'Ketumah', one may come to stoke the coals, or because it looks like cooking, and presumably, that is also why they forbid one to return even water on to a Kirah.

5)

(a)Chazal forbade Chazarah or even Shehiyah on a Kirah which is not 'Gerufah u'Ketumah' - because its heat increases (similar to Hatmanah, which is forbidden even on Erev Shabbos regarding things that increase their heat. See Tosfos, DH 'Lo Yiten').

6)

(a)In the Reisha of our Mishnah, the Tana writes 'Lo Yiten Ad she'Yigrof ... ' - which could mean 'Lo Yachzir', over which Beis Shamai and Beis Hillel subsequently argue (in which case, they will both agree that it is permitted to leave things on a stove to cook, even when it is not 'Gerufah u'Ketumah').Alternatively, it could mean 'Lo Yashhu', meaning that Beis Hillel will permit leaving something to cook only only an oven Kirah which is 'Gerufah u'Ketumah', but, according to Beis Shamai, even that is forbidden.

(b)If we explain the Mishnah to mean specifically "Lo Yachzir', inferring that leaving something to cook on the stove is permitted even when the stove is not 'Gerufah u'Ketumah' - then the author of the Mishnah will be Chananya, who maintains that, once the pot has reached the stage of 'Ma'achal ben D'rusai' (one third cooked), one may leave it on the stove to continue cooking (without G'rifah u'K'timah).

(c)The problem with interpreting the Mishnah like this is - that the Reisha and the Seifa of the Mishnah are both telling us the same thing (Chazarah to a Kirah which is G'rufah u'Ktumah).

(d)The Gemara amends the Mishnah to read 'Kirah' ... 'O Ad she'Yiten es ha'Efer - Aval Lishhos, Mashhin af-al-Pi she'Eino Garuf etc. u'Mah Hein Mashhin, Beis Shamai Omrin Chamin etc. ve'Hach Chazarah de'Amri Lach La'av Divrei ha'Kol Hi, Ela Machlokes Beis Shamai u'Veis Hillel, she'Beis Shamai Omrin' ... .