1.就近一致原则
(1)由or，not only...but also...，neither...nor...，either...or...，whether...or...，not...but...等连接两个或两个以上的并列主语时，通常根据就近一致原则，谓语动词要与离它最近的主语在数上保持一致。
Neither his parents nor I am able to persuade him to change his mind.
(2)here/there引导一个句子而主语又不止一个时，通常根据就近原则，谓语动词要与离它最近的主语在数上保持一致。
Here is a ruler，a few pencils and two copybooks.
2.意义一致原则
(1)谓语动词必须用单数的情况
①表示学科的名词以及works(工厂)，news(消息)等作主语时，虽然本身为复数形式，但表示单数意义时，谓语动词仍用单数。
Politics is his favorite subject.
②表示某些组织机构的名词、书/报名、国名、地名等作主语时，虽然形式上是复数，但所表示的意义是单数，所以谓语动词用单数。
Do you know when the United Nations was set up?
(2)谓语动词必须用复数的情况
表示总称意义的名词，如people，police，public，cattle等作主语时，谓语动词用复数。
The police are searching for the murderer.
(3)谓语动词的形式依据主语表示的意义而定
①集体名词，如family，class，group，team，club，company，government，population等作主语时，谓语动词的形式根据其在语境中表示的意义而定。当其表示集体意义，强调整体概念时，谓语动词用单数；当其表示集体中各个组成部分，强调个体概念时，谓语动词用复数。
As far as I know，his family is not very large but the family are all music lovers.
②“the＋形容词/分词”表示“一类人”时，谓语动词用复数。
The poor were looked down upon in the old days.
