"It is neither good nor bad."
Nor is used in negative constructions, for the second element of two items. It’s the opposite of or. For example, let’s say both of your sisters, Fay and Rita, are good at tennis. You can say, “Both Fay and Rita are good at tennis.” On the other hand, if they’re bad at it, you say, “Neither Fay nor Rita is good at tennis.” You can also use nor to connect two negative clauses: “I don’t want to go to the grocery store, nor do I want to babysit the kids.” Finally, just like the words “either” and “or” are often paired together: “Either ‘a’ or ‘b’ is correct,” (i.e., they’re both correct, you can choose either one), so the words “neither” and “nor” are paired: “Neither ‘a’ nor ‘b’ is correct,” which means they’re both wrong.