1）當there be 句型的主語是一系列事物時，謂語應與最鄰近的主語保持一致。

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）當either… or… 與neither… nor，連接兩個主語時，謂語動詞與最鄰近的主語保持一致。 如果句子是由here， there引導，而主語又不止一個時，謂語通常也和最鄰近的主語一致。

Either you or she is to go.

Here is a pen， a few envelops and some paper for you.