Question: Why didn't Rava ask about accepting a short (i.e. 30 day) Nezirus (after having accepted Nezirus after 20 days? Perhaps he begins the latter immediately, interrupts for the first Nezirus, and does not shave until finishing the last 10 days of the latter Nezirus?)

Answer: In truth, first he asked about a short Nezirus, and then about a 100 day Nezirus:

If you will say regarding a short Nezirus, that since only 10 days remain, they cannot join with the first 20 (so he did not want the Nezirus to start within the 20 days), perhaps when he accepted 100 days, since 80 days remain, they join to the first 20;

Or, perhaps even in this case he does not want to interrupt the Nezirus?

Question #2: If you will say that he starts right away, if he accepted Nezirus after 20 days, and to be a Nazir Olam right away, does the latter take effect right away? (Perhaps here we do not say so, for Nezirus Olam is a different kind of Nezirus, and it is an interruption.)

Question #3: If you will say that it does, since the Nezirus after 20 days can be annulled (by a Chacham) through regret, if he accepted Nezirus Shimshon after 20 days, and to be a Nazir right away, what is the law?

Nezirus Shimshon cannot be annulled. Does the (regular) Nezirus take effect?

Question #4: If one said 'I am like Moshe on the seventh of Adar' is he a Nazir? (Perhaps he refers to the die Moshe died, when many Yisraelim accepted Nezirus due to grief. Or, he refers to the day Moshe was born, a day of Simchah!)

Answer (to Question #1, 13b - Beraisa): If one said 'I will be a Nazir after 20 days, and I am a Nazir from now for 100 days', he counts 20 days (of the long Nezirus), then 30 days of Nezirus, then completes 80 days (of the long Nezirus).

(R. Yochanan): If (in this case of the Mishnah) he became Tamei while counting the Nezirus of his son, this also nullifies the days he counted towards his own Nezirus;

(Reish Lakish): The days he counted towards his own Nezirus stand.

R. Yochanan says that all the days are Batel, because they are like one long Nezirus;

Reish Lakish says the first days are not Batel, because it is like a separate Nezirus.

(R. Yochanan): If a Nazir became a Metzora Muchlat (he brought a Siman of absolute Tum'ah), and became Tamei Mes during this time, this cancels the days of Nezirus that he counted;

(Reish Lakish): The days are not Batel.

R. Yochanan says that they are Batel, because he is in the midst of Nezirus;

Reish Lakish says they are not Batel, because the period of being a (Metzora) Muchlat is distinct from the Nezirus.

They needed to argue in both cases:

Had they argued only about two Neziruyos, one might have thought that there R. Yochanan says all the days are Batel, since they are like one Nezirus, but he would agree with Reish Lakish that the days of Muchlat are distinct from the Nezirus.

Had they argued only about a Muchlat, one might have thought that there Reish Lakish says that the days stand, but he agrees with R. Yochanan about two Neziruyos.

(Rav): If a Nazir became Tamei on a day of growing his hair (he finished the Nezirus he accepted, but his hair was cut in the middle b'Ones, and he cannot shave until he has 30 days growth of hair), this does not nullify the days he counted.

Even R. Yochanan said that Tum'ah nullifies what he counted, only when he is in the midst of Nezirus. Here, he finished his Nezirus!

(Shmuel): This nullifies the days he counted.

Even Reish Lakish said that Tum'ah does not nullify the previous days, only when the previous days were a separate Nezirus. Here, it is all one Nezirus!

(Rav Chisda): All agree that if he became Tamei after bringing the Korbanos but before shaving, he has no solution.

Question: According to whom is this?

Suggestion: This is according to R. Eliezer.

Rejection: He holds that the Isurim of a Nazir are in effect until he shaves. It is as if he became Tamei within the term (and he has a solution, like any Nazir Tamei)!

Conclusion: It must be according to Chachamim.

Summation of question: Chachamim say that Isurei Nezirus go away even if he does not shave!

Answer: Really, it is like Chachamim. He has no solution to perform he Mitzvah of shaving properly (in Taharah, with the Korbanos).

(R. Yosi b'Rebbi Chanina): A Nazir who finished his term (and is ready to bring Korbanos) is lashed if he becomes Tamei, but not for shaving or drinking wine.

Question: Why is Tum'ah different?

Suggestion: It says "all the days (...he will not become Tamei)" to include the days after the term.

Rejection: Also regarding shaving and drinking wine, it says "all the days"!