Here are a few examples:
My cat seems in need for milk.
My friends and I were walking by the park when we saw Jim sitting in.
Joe as well as her friends is very playful.
Either Sally or her cousins are afraid of dogs.
Neither Sally's cousins nor she is afraid of cats.
In all of these sentences, we have used appropriate verb forms. The subject verb agreement rules that the singular subject needs a singular verb and plural subject, plural verb.
This rule is pretty obvious in simple sentences like the first two above, but the others seem to need some more clarification.
1. As Well As
When combining any two subjects with as well as, always agree the verb with the first subject. Examples:
Jim as well as his friends is a good swimmer.
Jim's friends as well as Jim are good swimmers.
Emmerich's films as well as Spielberg's are interesting to me.
2. Either (Neither) Or
When combining subjects with 'or', always agree with the subject nearest to the verb.
Either Bill or his family members have to approve it.
Neither his dogs nor his cat has any disease.
3. Agreement Related to Person
First and second persons always takes plural verb, except when using 'was' with first person.
I take it you granted the permission for the play?
I have found it interesting.
I was having my meal when you came in yesterday.
I was there but missed your performance.
Were you in college yesterday?
You are a good student.
Third person subjects always take the verb according to the number.
He is a good student.
Jim and Harry are good in singing.
They were talking about the latest movies.
These cats are mine, and that is Joe's.
4. Take the Actual Subject When Considering Verb Type
Some sentences such as the following may be misleading to most.
The apples bought by Joe, afterwards washed by Sarah, and eaten by Jim, are responsible for his illness.
Here, the subject of the verb is 'apples' and not Joe, Sarah, or Jim.
Carefully consider which is the subject before applying the verb. Here are a few such examples:
The rules set forth by the Indian Constitution don't allow internal transfer of money not done through any RBI approved authority.
The viewpoint of hundreds of members of the opposition reflects that of less than fifty per cent of the public.
The success rate of more than fifty schools and colleges in my state seems to be high.
5. Certain Collective Nouns Take Singular Verb
Certain nouns, which always have come together, may take singular verbs. Examples:
Bread and butter is what he takes in the morning.
That's it folks!
Here are a few examples: