Both / Either / Neither Parties
Both ... and
The paired conjunction 'both ... and' is used to introduce dual subjects which take plural verb conjugations.
Both the room assignments and the roommate assignments have been made.
Both ticket purchases and subscriptions are popular this year.
Either ... or
The paired conjunction 'either ... or' is used in sentences to show that one or the other is performing an action. Conjugate verbs based on the subject (singular or plural) closer to the conjugated verb.
Either Mary or Anne will handle complaints from customers.
Either the chain operators or the customers will win out.
Neither ... nor
The paired conjunction 'neither ... nor' is used in sentences giving a negative sense. Neither one nor the other subject does an action. The negative is conveyed by the 'n' in 'neither' and 'nor'. 'Not' is not placed before the verb. Conjugate verbs based on the subject (singular or plural) closer to the conjugated verb.
Neither the hotel manager nor the customer made it to the emergency exit.
Neither the front office procedure nor the computer system was updated.
Neither the pizza dough nor the olives are tasty.
Neither the atmosphere nor the menu items were tasteful.