I have two questions about French negation. I hope somebody can help me.
The first sentence "Je ne lis pas, ni n'écris" Why is there pas in the first part but not the second? Why is there ne after ni in the second? The second sentence "Il ne veut ni ne peut manger de la colle" Why is not there pas after the verb in the first part like the first sentence? Again what is this ni ne? Thanks.
The first sentence translates into English as "I do not read, nor do I write." (You can substitute "neither" for "nor.")
The second sentence translates into English as "He neither wants to nor can eat glue." (That's pretty awkward; it would be better re-cast as "He doesn't want to eat glue, nor can he")
To answer your questions is beyond my knowledge, but here is what Grevisse and Gosse have to say in "Nouvelle grammaire française":
"Ni" se répète d'habitude devant chacun des termes coordonnés (le verbe est alors accompagné de la négation simple "ne"):
Elle ne viendra ni aujourd'hui ni demain.
Cependant, "ni" se place seulement devant le second terme quand celui-ci apporte une sorte de précision supplémentaire (et la négation est alors "ne ... pas"):
Les cassolines ne doivent pas coûter cher, ni les parfums qu'on y chauffe. (Étiemble)
I hope this helps.
In the first Grevisse and Gosse example, the two coordinates are adverbs: aujourd'hui and demain. In their second example, the two coordinates are nouns: cassolines and parfums. But in the examples you give, the coordinates are verbs: lis and écris in the first, and veut and peut in the second.
'Pas' is missing in the second sentence because the style is literary. We cannot always drop the 'pas' in the formal style, but in this case it was possible. It could have been, 'Il ne veut pas ni ne peut manger de la colle', but the version you have found sounds better.
The first sentence is a bit awkward. Is it complete?
I took both sentences from the notes section of the negation lesson. Both are weird sounding to a learner. I think they should not have been added or at least have explanations because they are confusing.
Here is the text copied verbatim from the "Negatives" notes:
When ni coordinates multiple conjugated verbs, each verb must be preceded by ne.<pre>
Je ne lis pas, ni n'écris. — I don't read or write. Il ne veut ni ne peut manger de la colle. — He neither wants nor is able to eat glue.</pre>