Rav Ashi holds like Reish Lakish, and answered the question according to R. Shimon. Ravina holds like R. Yochanan, and answered the question like Chachamim.

Answer #2 (Rav Ashi): The Reisha said that if the Choletz was Mekadesh the Choletzes (and he died), she needs Chalitzah from the brothers. This refers to brothers who were born later. It is like R. Shimon (who permits Eshes Achiv she'Lo Hayah b'Olamo. She may not do Yibum, for she was forbidden to her husband, all the more so to her Yavam - Tosfos.)

The Seifa says that if a brother was Mekadesh her, she has no claim against him. This refers to a brother who was already born, like Reish Lakish taught.

Answer #3 (Ravina): The Reisha says that if the Choletz was Mekadesh the Choletzes, she needs Chalitzah from the brothers. This refers to brothers who were already born, like R. Yochanan taught.

The Seifa says that if a brother was Mekadesh her, she has no claim against him. This refers to brothers who were born later. It is like Chachamim (who argue with R. Shimon).

(Rav Acha or Ravina): If a man did Yibum, then a brother did Yibum with a Tzarah, the second marriage is forbidden with Kares;

(The other of Rav Acha and Ravina): It is only Chayavei Aseh.

The opinion that is Mechayev Kares holds like Reish Lakish. The opinion that it is only an Aseh holds like R. Yochanan.

(Rav): The Tzarah of a Sotah is forbidden (and even exempt from Chalitzah). She is called Tamei, like Arayos.

Question (Rav Chisda - Mishnah - R. Shimon): Bi'ah or Chalitzah (of a Sotah) with a brother exempts her Tzarah.

Answer: Rav discusses a Sotah mid'Oraisa, but the Mishnah explicitly discusses a 'Sotah mid'Rabanan' (a woman who remarried in the life of her husband after one witness testified that her husband died. She did not intend to sin, but she is fined because she did not check well that he really died.)

Question: The answer is obvious. Why did Rav Chisda ask?

Answer: He holds that Rabbinic enactments are made similar to Torah law.

Question (Rav Ashi - Mishnah): If she was secluded (with the man she was warned about) long enough to have Bi'ah, she is forbidden to her husband and forbidden to eat Terumah. If her husband dies, she does Chalitzah but not Yibum. (Rav exempts even her Tzarah from Chalitzah!)

Answer: Rav discusses a Vadai Sotah (she definitely had Bi'ah). The Mishnah discusses a Safek Sotah.

Question: Does he say that a Vadai Sotah is different because she is called Tamei? Also a Safek Sotah is called Tamei!

(Beraisa - R. Yosi ben Kipar): If a man was Machazir Gerushaso from Nisuin (divorced his wife and remarried her after she fully remarried and was widowed or divorced from her new husband), he is forbidden to her. If she merely was Mekudeshes to someone else, she is permitted - "Acharei Asher Hutama'ah";

Chachamim forbid in both cases. "Acharei Asher Hutama'ah" refers to a Sotah that was in seclusion.

Answer: 'Seclusion' is a euphemism for Zenus (but a Safek Sotah is not called Tamei).

Question: If she was Mezaneh, Tum'ah is explicitly written (in Parashas Sotah itself) - "V'Nisterah v'Hi Nitma'ah"!

Answer: "Acharei Asher Hutama'ah" forbids her with a Lav.

R. Yosi ben Kipar holds that there is no Lav regarding a Sotah, even if she was Mezaneh.

This is because "Kidushin" and "marriage" are written (regarding Machazir Gerushaso (Rashi) or "Acharei Asher Hutama'ah (Tosfos), therefore we do not include Zenus).

Question (Rav Yehudah): If a man was Machazir Gerushaso after she remarried and he died, what is the law of her Tzarah?

Version #1: We do not ask according to R. Yosi ben Kipar. Since Tum'ah is written regarding Machazir Gerushaso (she is like Ervah, so), her Tzarah is like her.

Suggestion: Perhaps "To'evah Hi" teaches that she is an abomination, but her Tzarah is permitted (to do Yibum)!

Rejection: No. "Hi" excludes her children (they are Kesherim), but her Tzarah is also To'evah (forbidden to do Yibum).

The question is according to Chachamim.

Even though they say that Tum'ah written regarding Machazir Gerushaso refers to a Sotah, the simple meaning of the verse is not uprooted;

Or, perhaps once it is uprooted, it is entirely uprooted!

Version #2: We do not ask according to Chachamim. Once the verse is uprooted, it is entirely uprooted;

We ask according to R. Yosi ben Kipar.

Even though it says Tum'ah regarding Machazir Gerushaso, it says "To'evah Hi". She is To'evah, but her Tzarah is not.

Or, perhaps she is To'evah, but her children are not. However, her Tzarah is also To'evah. (End of Version #2)

Answer (Rav Sheshes - Mishnah): If one widow was Kesherah and the other Pesulah, if he does Chalitzah, he does it with the Pesulah. If he does Yibum, he does it with the Kesherah.

Question: What do Kesherah and Pesulah refer to?

They cannot mean permitted and forbidden to all (Kohanim, and the Yavam is a Yisrael). Since she is permitted to him, it makes no difference to him!

Answer #1: Rather, it means permitted and forbidden to him, i.e. the dead brother. He was Machazir Gerushaso, and the Mishnah permits Yibum with the Tzarah!

Rejection (and Answer #2): Really, they mean permitted and forbidden to Kohanim;

Even though it makes no difference to him, Rav Yosef taught that one should not spill out water that others could use. (He should not do Chalitzah to the widow permitted to Kohanim, since this would forbid her to Kohanim.)

Answer (Beraisa): If one was Machazir Gerushaso after she married, she and her Tzarah do Chalitzah.

Objection: This cannot be!

Answer: It must mean that she or her Tzarah does Chalitzah. (This answers our question.)

Rejection: In any case the Beraisa must be corrected. We can correct it to say that she may do only Chalitzah, but her Tzarah may do Chalitzah or Yibum.

Version #1 - Question (R. Yochanan): If one was Machazir Gerushaso after she married, what is the law of her Tzarah?

R. Ami: Why don't you ask about her?

R. Yochanan: Her law is clear from a Kal va'Chomer:

She became forbidden to the one she was permitted to (her husband). All the more so she is forbidden to the one she was forbidden to (the Yavam)!

He asks about her Tzarah.

Is the Kal va'Chomer strong enough to forbid the Tzarah, or not?

Version #2 - Rav Nachman - Question (R. Yochanan): If one was Machazir Gerushaso after she remarried, what is her law?

R. Ami: Why don't you ask about her Tzarah?

R. Yochanan: The law of her Tzarah is clear. The Kal va'Chomer is not strong enough to forbid the Tzarah;

The question is regarding her. Is the Kal va'Chomer strong enough to block the Mitzvah of Yibum, or not?