1)
What is the meaning of "Vayatzel"?
1.
Refer to 11:17:3:1 & 2.
2)
What does the Pasuk mean when it writes "Vayisnab'u ve'Lo Yasafu"?
1.
Rashi #1: It means that they only prophesied on that day and no longer.
2.
Rashi #2 (citing Targum Onkelos) and Targum Yonasan: It means that they prophesied now and did not stop prophesying.
3.
Ramban (on Pasuk 17): It means that they only prophesied what Hashem spoke to Moshe, 1 but not first-hand.