USAGE NOTE 用法说明: either … or and 和 neither … nor
Use a singular verb with these words when you are writing if the second noun is singular. 如果第二个名词是单数，这些词使用时动词用单数形式:
If either Doris or Meg calls, please take a message. 如果多丽丝或梅格来电话，请帮忙记录一下口信。
Neither Theo nor Garth is very tall. 西奥和加斯长得都不太高。
If the second noun is plural, use a plural verb. 第二个名词如果是复数，动词要用复数形式:
If either my sister or my parents come, please let them in. 我姐姐或者我父母来的话，请让她［他们］进来。
However, in informal speech, people usually use a plural verb, whether the noun is singular or plural. 但在非正式的口语中，人们通常不论第二个名词是单数还是复数，都使用动词的复数形式。