Opinion #1 (Rashi): This refers to after 30 days.

Support: Presumably, this is like the Seifa, in which he says "I had Bi'ah [with her]", and she says "I did not have Bi'ah [with him]." Even so, she needs a Get and Chalitzah;

This is only after 30 days, for the Reisha connotes that within 30 days she does not need a Get;

It teaches that we force him to do Chalitzah. It does not teach that she needs a Get.

Opinion #1 (cont.): Likewise, the clause in which she says "I had Bi'ah" is after 30 days, but within 30 days, she needs Chalitzah.

If it referred to also within 30 days, it should have been taught also above, regarding within 30 days, lest we err to establish it only after 30 days, like the Seifa.

Consequence: Based on this, we cannot explain [like Rashi] what it says below "because we force and request, will we forbid her Tzarah?!"

Explanation #1 (Rashi, R. Chananel): Because we force within 30 days, and request after 30 days, will we forbid her Tzarah?!"

Objection: Why is her (Leah's) Tzarah permitted within 30 days? She (Leah) herself, if she said that she had Bi'ah within 30 days, needs Chalitzah;

All the more so her Tzarah, who does not know about [whether Leah had] Bi'ah like she (Leah) knows, we should forbid her without Chalitzah!

Explanation #2: Rather, below we permit her Tzarah only after 30 days.

"We force him" when he said "I had Bi'ah", and retracted and said "I did not have Bi'ah", similar to the Seifa of the Beraisa;

However, if he did not initially say "I had Bi'ah", rather, both of them agree from the beginning to the end that he did not have Bi'ah, even after 30 days the Tzarah is not permitted.

Proof: The Seifa connotes that only when he initially said "I had Bi'ah", she needs a Get;

However, if initially he said "I did not have Bi'ah", she does not need a Get.

Suggestion: We permit the Tzarah [even] when both of them agree that he did not have Bi'ah, for we establish her like a Vadai Be'ulah.

Rejection: She does not need a Get!

Defense of Suggestion: However, we can say that she also needs a Get, even if both of them agree that he did not have Bi'ah.

Implied question: [If so,] why does it mention that he said "I had Bi'ah", and later he retracted...? The same applies even if he said "I did not have Bi'ah", she needs a Get!

Answer: It mentioned that initially he said "I had Bi'ah" to teach that even so, we force him to do Chalitzah;

This is unlike Rashi and R. Chananel explained (Explanation #1), that we do not force [after 30 days].

Opinion #2 (and defense of Explanation #1): We can even say that below, we permit the Tzarah even within 30 days, like Rashi and R. Chananel explained, and 'he said "I did not have Bi'ah"' refers also to within 30 days;

Similarly the Seifa, in which he said "I had Bi'ah", applies also within 30 days. Even if both of them agree that he did not have Bi'ah, she needs a Get with Chalitzah, even within 30 days.

Note: This is unlike Opinion #1 above of Rashi.

It was not precise that the Gemara mentioned that he said "I had Bi'ah", like I explained.

Opinion #2 (cont.): The Reisha teaches that we force him to do Chalitzah. She also needs a Get, like the Seifa teaches;

However, it did not yet come to teach the enactment of a Get with Chalitzah, rather, the law of forcing and requesting Chalitzah.

Pesak: Due to the two versions that I explained, it seems that we should forbid the Tzarah until after 30 days, unless both of them agree that he had Bi'ah;

Also, we should obligate a Get for a Kenusah (one who entered his house), even within 30 days, even if both of them agree that he did not have Bi'ah.

Implied question: Why didn't he establish this Beraisa like Mishnah Acharonah (above, 39b), which says that Mitzvas Chalitzah has precedence [over Yibum]. Therefore, we force him to do Chalitzah!

Answer: He discusses our Mishnah, which discusses laws of Yibum according to Mishnah Rishonah.

Note: Tosfos did not ask against Rav, who clearly discusses our Mishnah, for it was clear to Tosfos that our Mishnah is like Mishnah Rishonah. He asked against R. Ami, for it seems that he discusses the Beraisa.

Explanation: This refers to the Get she already has.

Question: If so, how do we understand "even though he retracted and said "I did not have Bi'ah", she needs a Get and Chalitzah?

Just the contrary! [In any case she already has a Get, and] because he said "I did not have Bi'ah", this is why she needs Chalitzah!

Answer (Ri): It means that even though he said "I did not have Bi'ah", she needs a Get for a proof, for she cannot marry through Chalitzah alone.

Explanation #1 (Rashi): It is known to Shamayim that he cannot have Bi'ah with me like normal men.

Rejection (and Explanation #2): In Nedarim (91a), the Gemara clearly explains that his semen does not shoot like an arrow (so he cannot father children).

Explanation #1 (R. Tam): They will pray to Hash-m, and He will give children to them.

Explanation #2 (R. Chananel): He will make a Seudah and appease her. The Yerushalmi says so.

Explanation #1 (Rashi): Is she forbidden to the Yavam due to this vow? Does it cross her mind that her husband will die, and she will fall to him [for Yibum], and she is forbidden to him?

Or, it does not cross her mind, and she did not forbid herself to him?

Objection #1 (Ri): Obviously, she forbade herself to all men!

Objection #2: Why does the Gemara say "[perhaps] he is not like her husband"? It should say [perhaps] he is not like other men!

Objection #3: Why does it say "this teaches that we force, like Rav"? She is permitted to him!

Explanation #2: The question is whether it crosses her mind to forbid herself to the Yavam, and we request that he do Chalitzah?

Or, perhaps she did not [vow] in order to forbid herself to her Yavam, like to her husband?

Rav says that the Yavam is not like her husband. It did not cross her mind to forbid herself to the Yavam, like to her husband, therefore we force him to do Chalitzah to her;

Shmuel says that the Yavam is like her husband, so we request that he do Chalitzah. It crossed her mind to forbid herself to her Yavam.

Conclusion: I say that this opinion is primary.

Implied question: This is obvious!

Answer: Since it taught that he can divorce, it taught that he can keep her.

Explanation: Rabanan brought her (a Pikachas who became deaf after she married) to the Beis Midrash to prove their opinion, and said to him "even this [woman] has the same law."

Question: According to R. Yochanan ben Nuri, why can't she be divorced? She does not return [to her husband] when we gesture to her!

Answer: In any case, at the time he gives the Get, he sends her and she returns. She does not understand [that she is divorced] until they expel her b'Al Korchah (against her will).

Alternate text: [Some texts of the Mishnah say] "about a Ketanah Bas Yisrael, that she eats Terumah", like in the Gemara in Gitin (55a).

Rebuttal: There is no need for this text here. They brought the testimony only to prove their opinion. Why should they mention a Ketanah [eating Terumah]?

Distinction: However, if she was already married to him, Chachamim enacted that he may not divorce her, since she does not know to guard herself, like below (113b).