Here are a few more rules to follow under Subject-verb agreement:

• When the subject is preceded by each and every, the following verb is usually singular.

For example: Every man is entitled to certain fundamental rights.

Each of the candidates was asked to bring the related documents.

• When two or more subjects are connected using either-or/neither-nor, the verb must be in agreement with the nearest subject.

For example: Neither the orchestra nor the singers were able to reach the venue on time.

Either she or I am going to Singapore for this project.

• With somebody, nobody and none, only singular verb is used.

For example: Nobody has returned the books.

None was able to cross that bridge.

• Words like trousers and scissors, in which two components are always taken together, take singular verbs.

For example: My new pair of trousers is blue.

This pair of spectacles belongs to him.