Negative pairs: neither...nor, either...or, not...either
Either X or Y (positive choice)
Neither X nor Y (both negative); Not X either
Do you want either X or Y?
💡 Neither...nor is already negative; don't add 'not'. Verb agrees with nearest subject.
✓Neither the teacher nor the students were ready.
✗Neither the teacher nor the students was ready.
Verb agrees with nearest subject (students = plural).
✓I don't like coffee. I don't like tea either.
✗I don't like coffee. I don't like tea neither.
Use 'either' with 'don't', not 'neither'.
✓Neither of them knows the answer.
✗Neither of them don't know the answer.
Neither is already negative.