Explanation #1 (Rashi): This is like "[you are Mekudeshes to me] on condition that I am a Kohen", and he was found to be a Levi.

Question: If so, how can we ask that also the Reisha is Nisu'ei Ta'os? We say below that there is no Tenai in Nisu'in!

Explanation #2 (Ri): Kidushei Ta'os is that she thought that her husband died, but really he did not die; like is actually true;

According to this, the Gemara properly asked that also the Reisha is Nisu'ei Ta'os. (Also there, she thought that her husband died!)

Question: Why don't we say that Kidushei Ta'os in the Reisha is [on condition that he is] a Kohen, and he was found to be a Levi, therefore we cannot ask from the Reisha, because there is no Tenai in Nisu'in!

Answer (Ri): Kidushei Ta'os is not common. We are not concerned lest people attribute [her second marriage] to Kidushei Ta'os;

Only R. Akiva is concern for it below (94b), regarding "R. Akiva adds even Eshes Ach and Achos Ishah." Rabanan are not concerned.

Implied question: We hold that Kesuvah is mid'Oraisa! We write in Kesuvos "200 Zuz that are proper for you mid'Oraisa"!

Answer (Ri): The Gemara means "why did Chachamim enact a Kesuvah for a widow?" All agree that [her Kesuvah] is only mid'Rabanan. It was so that it should not be light in his eyes to divorce her;

Also here, even a Besulah, who has a Kesuvah mid'Oraisa, we fined her [to forfeit her Kesuvah], so it will be light in his eyes to divorce her!

Support: We find like this below (90b) regarding annulling vows;

Some texts say "why did Chachamim say that a husband can annul his wife's vows", even though mid'Oraisa he can annul her vows!

Rather, it means that "why did Chachamim say that a husband can annul in cases that mid'Oraisa he cannot", like the case above (29b) of a Shomeres Yavam;

It says [there] that it is like Rav Pinchas taught, that every [wife] vows with intent for her husband (it should be a vow only if he approves), so she will not be repulsive to him;

Since there is the reason of being repulsive to him, if so, even when mid'Oraisa [he can annul], like here, Chachamim said that he cannot annul, so she will be repulsive to him!

Explanation #1 (Rivan): This is because it says "Titen Lo" (give to the Kohen something he may eat), and not [something permitted only] for his fire.

Rebuttal: This cannot be! In Pesachim (33a), it asks on this teaching "if he tithed [Tamei on Tahor] b'Shogeg, it is Terumah;

Citation (33a) Question: What is the reason? We should say "Lo", and not for his fire!

Citation (cont.) Answer: B'Shogeg it is Terumah if it once was Kosher;

'"Titen Lo", and not for his fire' applies to if it was never Kosher, e.g. it became Chametz while attached, or a Tamei person detached it while there was liquid Tofe'ach (enough to wet something else) on it. (It was Huchshar and became Tamei the moment it was detached.)

Summation of question: There, even b'Di'eved it is not Terumah!

Explanation #2: Here, l'Chatchilah it is not Terumah due to a loss to the Kohen, like Rashi explained.

Explanation #3: When it once was Kosher, Chachamim decreed l'Chatchilah not to make it Terumah, due to when it was never Kosher;

Explanation #4 (Ri): Due to "Kol Chelbo", one must separate Terumah from what is good. Tamei on Tahor is from the bad on the good.

Implied question: If one separated from the bad on the good, even b'Mezid, it is Terumah, and he need not tithe again!

A Mishnah (Terumos 2:6) says that [if one separated] from the bad on the good, it is Terumah. It does not teach that he must tithe again!

Answer: Chachamim were more stringent about Tamei, for it cannot be eaten at all. Bad produce is somewhat edible.

Support: This is why if one separated a gourd for Terumah and it was found to be bitter, he must tithe again, for it is not proper to eat. This is unlike other cases of bad [Terumah];

This is clear from the Yerushalmi, which calls it Safek food.

Explanation: We discuss when he was Shogeg. This is clear from our Sugya.

Question: When one tithes wine on wine, and it is found to be vinegar, it is not Terumah because he did not intend to make vinegar Terumah;

Citation (Terumos 3:1 - Mishnah): If one separated a barrel of wine to be Terumah, and it was found to be vinegar, if it is known that it was vinegar before he tithed, it is not Terumah.

Also regarding [bitter] gourds, why is it Terumah? He did not want to make such bad Terumah!

Suggestion: That Mishnah is like Rebbi, who says that wine and vinegar are two [different] species (Bava Basra 84b).

Rejection: If so, even if he intended to tithe vinegar on wine, or wine on vinegar, it would not be Terumah!

Source - Citation (Terumos 2:4 - Mishnah): One may not tithe from a species on another species. If he did, it is not Terumah.

This is even if he tithed good on bad, like it says there.

Answer (Ri): Wine and vinegar, even though they are one species, they are two different names. This is wine, and this is vinegar. Therefore, this is a big mistake, and it is not Terumah;

However, a gourd that was found to be bitter is not such a big mistake. He intended for a gourd, and it is a gourd!

Similarly, from Tamei on Tahor, b'Shogeg it is Terumah. He tithed that [species] which he intended for.

Implied question: The Tosefta connotes that the case of vinegar on wine is not Terumah is like Rebbi!

It concludes explicitly "these are Rebbi's words, for Rebbi says that wine and vinegar are two species. Chachamim say that they are one species.

Answer: Perhaps according to Chachamim, who say that they are one species, when in the east intends to tithe wine, and it is found to be vinegar, it is Terumah and he must tithe again, just like one who separated a gourd, and it was found to be bitter.

Even according to Rebbi, if he intentionally tithed from vinegar on wine, it is Terumah, for mid'Oraisa they are one species.

Support: The Yerushalmi in Terumos (2) connotes like this. Rebbi argues with R. Yishmael b'Rebbi Yosi, who said in the name of his father that we may tithe wine on vinegar. Rebbi said that we do not tithe;

R. Yehoshua ben Levi said, presumably Rebbi agrees about Torah law. Rebbi holds that if you permit to tithe wine on vinegar, he (one who heard this) will think that one may tithe vinegar on wine.

Implied question: Generally, we do not decree not to tithe from good on bad, lest people come to tithe from bad on good!

Answer: There is more concern regarding vinegar, for some people prefer vinegar to wine, like it says there in Bava Basra.

Implied question: Why did Rebbi say that they are two species? (He agrees that it is one species, just Chachamim decreed!)

Answer: He means that Chachmah made them like two species, and it is not Terumah when he erred, i.e. he intended for wine and it was found to be vinegar.

Explanation: Therefore, Chachamim made it as if he did not tithe at all. The measure [that he declared to be Terumah] reverts to be Tevel;

If you would say that it is Terumah, he will come to transgress, for he acted like a Rasha.

When he was Shogeg, he did not intentionally do an Isur. He is not suspected to transgress. Rivan explained like this.

Explanation #2: When he was Shogeg, he did not do an Isur, so [Chachamim] did not fine him. When he was Mezid, they fined him.

Rejection: This is not a fine that it reverts to be Tevel. It seems more like a fine if we said that [it is Terumah and] he must tithe again, that he must tithe [and give away] two Terumos.

Explanation: He should separate on a tiny amount from it itself, in order to taste it, but no more. (He should not separate to exempt more than a tiny amount until tasting it.)

Explanation: He says that his separation has no effect to permit the remainder, but it is Terumah, and it fixes the measures he separated. (It is Terumah.)

[The Gemara asks] why is this different than the Mishnah of [tithing produce that grew in a flowerpot] with a hole on [what grew in a flowerpot] without a hole...?

In the latter case, the measure itself is not fixed, for mid'Oraisa it is not Terumah;

Also here, from Tamei on Tahor, since mid'Oraisa it is not fixed, like we are thinking now, why mid'Rabanan do we make it fixed, to uproot the Torah Isur?

Explanation (cont.): However, according to Rav Chisda, who says that it is Tevel, it is fine (this is like with a hole on without a hole).

Implied question: B'Shogeg, why is it Terumah?

Answer: This is because the verse is particular only about one who was Mezid, like it says "v'Lo Sisa Alav Chet", which connotes Mezid, in which he bears sin;

If he was Shogeg, it is Terumah.

Question: When he separates Tamei on Tahor, what difference does it make that it is Terumah and he need not tithe again the measure? In any case one may not eat it!

Answer: This is relevant to burning it. One may burn Tamei Terumah, but one may not burn Tamei Tevel, like it says in Shabbos (26a).

Explanation (Rivan): It is Terumah only regarding that one must give it to a Kohen, but not for anything else. It is not forbidden to Zarim.

Rebuttal (and Explanation #2 - Ri): Since it exempts [what grew in a pot] without a hole, which is obligated mid'Rabanan, it is Terumah mid'Rabanan, just [one who tithed what grew in a pot] without a hole on without a hole!

Explanation (Ri): He cannot separate from it itself, lest a Zar come to eat the remainder. (This is like the Ri explained in the previous Tosfos, that it is forbidden to Zarim.)

Since he called it Ma'aser, people will not be careful to guard it like Terumah.

Mid'Rabanan, the entire measure is Terumah, for it fixes the pot without a hole.

Explanation #1 (Rashi): This is when she reaches adulthood through years and bringing two hairs.

Rebuttal: The words connote unlike this. If so, it should have said "when she matures"!

Explanation #2 (Ri): Rather, "when she stands in her height" means that she looks a bit big, even though she did not reach adulthood, since she looks like his wife;

However, as long as she looks small, Chachamim's words would look ludicrous if he inherited her.

Explanation: We are thinking that just like Beis Hillel do not require that she look a bit big, which Beis Shamai require, also Beis Shamai do not require that she enter Chupah, which Beis Hillel require.

Explanation: The same applies if she entered Chupah and afterwards she [grew and] looks big. The Chupah from when she was small helps;

Rhetorical question: Why should this be different than Kidushin? Kidushin from when she was small helps for after she gets big!

Question: Still, since a minor's actions have no effect, how does the Chupah she did when she was a minor help?

Answer #1: Since she is in her husband's house, this is like Mesirah (being handed over) for Chupah, when she will have Bi'ah in adulthood for the sake of Kidushin;

Even if you will say that Bi'ah makes only Eirusin [but not also Chupah], she is immediately considered a Nesu'ah, just like one who owned a Chatzer on the road, and she entered with him for the sake of Nisu'in.

Answer #2: Since the Kidushin is in her adulthood, and mid'Oraisa an Arusah may eat Terumah, here the Chupah that was when she was a minor helps;

There is no concern for Simpon (a blemish that invalidates Kidushin) or Ula's concern (lest she feed Terumah to her siblings), since she is in her husband's house.

Explanation: He inherits her because Hefker of Beis Din is Hefker.

Implied question: Regarding Tamei [separated to be Terumah] on Tahor, why can't we say that Chachamim removed it from the owner's Reshus at the time of separation? (What forced Rav Chisda to say that Chachamim uprooted a Torah law?)

Answer: We cannot say so, for afterwards it is still his and he needs to tithe it.

Inference: Whenever he inherits her, he becomes Tamei for her, for she is a Mes Mitzvah.

Consequence: A widow to a Kohen Gadol, or a divorcee or Chalutzah to a Kohen Hedyot, he does not inherit her, for we say below (90b) that one does not become Tamei for a Pasul wife.

If he inherited her, he would become Tamei for her, just like for a Mes Mitzvah!

Retraction: You are forced to say that one does not depend on the other!

Proof #1: If one was married through Beis Din (based on one witness), and afterwards her husband came, we say that he (either husband) is not Metamei for her, even though her first husband inherits her. Chachamim did not fine him!

Implied question: He (her first husband) does not receive her Metzi'os (Hefker things she finds) or earnings!

Answer: This is because we fined her (like we explain below, 90b). However, why should her husband lose his inheritance?!

Proof #2: If so, a Kohen Gadol or Nazir would be permitted to become Tamei for their relatives and all whom they inherit when they are the only heir, and similarly for their wives! (A husband is always the sole heir of his wife, either mid'Oraisa or mid'Rabanan.)

Proof #3: According to the opinion (Kesuvos 83a) that a husband inherits his wife mid'Oraisa, why do we need a verse to teach that a husband becomes Tamei for his wife? This is obvious, for she is a Mes Mitzvah!

Explanation (Ri): Inheriting her does not make her a Mes Mitzvah;

Rather, it is because Chachamim have the power to uproot a matter from the Torah in a matter that seems [not to uproot], like I explained above (88a DH mi'Toch);

Since (her family) do not inherit her, she resembles a Mes Mitzvah. However, she is not a real Mes Mitzvah.

Support: If he becomes Tamei for her because she is a real Mes Mitzvah, how could he become Tamei for her where there are Yisre'elim [willing to bury her]?

Regarding a Mes Mitzvah, if there are a Kohen and Yisrael there, we say (Nazir 47a) that the Yisrael becomes Tamei, and not the Kohen!

Regarding a minor married mid'Rabanan, it connotes that he becomes Tamei for her like a [standard] husband who becomes Tamei for his wife mid'Oraisa, [even] if there are many Yisre'elim there.

Suggestion: From what we say below (90b) that neither husband annuls her vows, so she should become repulsive, we can prove that one cannot annul vows of his Pasul wife, e.g. a widow to a Kohen Gadol!