I can only dig up 13 rules... and most of them are very complicated... good luck...
Basic Rule. The basic rule states that a singular subject takes a singular verb while a plural subject takes a plural verb. The trick is knowing whether the subject is singular or plural. The next trick is recognizing a singular or plural verb.
Hint: Verbs do not form their plurals by adding an s as nouns do. In order to determine which verb is singular and which one is plural, think of which verb you would use with he or she and which verb you would use with they.
Exampletalks, talk Rule 1. Two singular subjects connected by or or nor require a singular verb.
Which one is the singular form? Which word would you use with he? We say, "He talks." Therefore, talks is singular. We say, "They talk." Therefore, talk is plural.
Example My aunt or my uncle is arriving by train today.Rule 2. Two singular subjects connected by either/or or neither/nor require a singular verb as in Rule 1.
Examples Neither John nor Susan is available.Rule 3.When a singular subject is connected by or or nor to a plural subject, put the plural subject last and use a plural verb.
Neither she nor I am going to the festival.
NOTE: Am is singular and agrees with the subject closest to it.
ExampleThe book or the magazines are on the shelf.Rule 4. When either/or or neither/nor connect a singular and plural subject, put the plural subject last and use a plural verb as in Rule 3.
Example Neither John nor the others are available.Rule 5. As a general rule, use a plural verb with two or more subjects when they are connected by and.
Example A car and a bike are my means of transportation.Rule 6. Sometimes the subject is separated from the verb by words such as along with, as well as, besides, not, etc. Ignore these expressions when determining whether to use a singular or plural verb.
Examples The politician, along with the newsmen, is expected shortly.Rule 7. The pronouns each, everyone, everybody, anyone, anybody, someone, and somebody are singular. Do not be misled by what follows of.
Excitement, as well as nervousness, is the cause of her shaking.
Examples Each of the girls sings well.NOTE: Everyone is one word when it means everybody.
Every one of the cakes is gone.
Rule 8. With words that indicate portions—percent, fraction, part, majority, some, all, none, remainder, etc.—you must look at the object of the preposition to determine whether to use a singular or plural verb. If the object of the preposition is singular, use a singular verb. If the object of the preposition is plural, use a plural verb.
Examples Fifty percent of the pie has disappeared. Rule 9. When either and neither are subjects, they take singular verbs.
Pie is the object of the preposition of.
Fifty percent of the pies have disappeared.
Pies is the object of the preposition.
One third of the city is unemployed.
One third of the people are unemployed.
All of the pie is gone.
All of the pies are gone.
Some of the pie is missing.
Some of the pies are missing.
Example Neither of them is available to speak right now.Rule 10. The words here and there are never subjects because they are not nouns. In sentences beginning with here or there, the true subject follows the verb.
Examples There are four hurdles to jump.Rule 11. Use a singular verb with sums of money or periods of time.
There is a high hurdle to jump.
ExamplesTen dollars is a high price to pay.Rule 12. If the pronoun who, that, or which appears as the subject in the middle of the sentence, you must decide whether to follow it with a singular or plural verb. In order to decide, look at the noun directly in front of the who, that, or which. If it is singular, use a singular verb. If it is plural, use a plural verb.
Five years is the maximum sentence for that offense.
Examples She is the secretary who write/writes the letters.Rule 13. Collective nouns such as team and staff may be either singular or plural depending on their use in the sentence.
The word in front of who is secretary, which is singular. Therefore, use the singular verb writes.
He is one of the men who does/do the work.
The word in front of who is men, which is plural. Therefore, use the plural verb do.
Examples The staff is in a meeting. Staff is acting as a unit here.
The staff are in disagreement about the findings. The staff are acting as separate individuals in this example.