1)当there be 句型的主语是一系列事物时,谓语应与最邻近的主语保持一致。
There is a pen, a knife and several books on the desk..
There are twenty boy-students and twenty-three girl-students in the class.
2)当either… or… 与neither… nor, 连接两个主语时,谓语动词与最邻近的主语保持一致。 如果句子是由here, there引导,而主语又不止一个时,谓语通常也和最邻近的主语一致。
Either you or she is to go.
Here is a pen, a few envelops and some paper for you.