Some Important Rules of English Grammar.

Infinitive to is not used after needn't and daren't.

Ex. He daren't to come here. (Wrong)

He daren't come here. (Right)

With pair words, always singular verbs are used.

List of some pair words is as follows.

Bread and butter, Rice and Curry, Hammer and Sickle, Slow and Steady, Truth and Honesty, Horse and Carriage, Crown and Glory, Rise and Fall, Coming and Going, Screaming and Shouting, Age and Experience, Eggs and Bacon, Ham and Eggs, Long and Short, Sum and Substances, Bag and Baggage etc.

Ex. Bread and butter are my favourite breakfast. (Wrong)

Bread and butter is my favourite breakfast. (Right)

Note: But if the pair words, used as a subject, represent a class then plural verb should be used.

Ex. Time and tide waits for none. (Wrong)

Time and tide wait for none. (Right)

Fire and water does  not agree. (Wrong)

Fire and water do not agree. (Right)

Gold and silver is precious metals. (Wrong)

Gold and silver are precious metals. (Right)

If two singular nouns connected with and and before the first singular noun, articles or possessive adjectives (my, your, our.......etc.) are used then in such sentences singular verb is used.

Ex.- The Principal and Secretary was there. (Right)

The Principal and Secretary were there. (Wrong)

My uncle and guardian has come to see me. (Right)

My uncle and guardian have to see me. (Wrong)

If two singular nouns are joined with and and before each singular noun, articles or possessive adjectives are used then they denotes two different people, so in such sentences plural verbs are used.

Ex. The Principal and The Secretary were there. (Right)

The Principal and the Secretary was there. (Wrong)

If two adjectives, which are connected with and, used before a singular common noun and before first adjective, indefinite articles a/an are used then in such sentences singular verbs are used because they denotes a single person.

Ex. A black and white cat was mewing. (right)

A black and white cat were mewing. (Wrong)

Note: But if before each adjective, indefinite articles (a/an) are used, then the structure of Sentence will be :A/an +adjective+and+a/an+adjective+ singular common noun + plural verb 

Ex. A black and a white cat were mewing. (Right)

A black and a white cat was mewing. (Wrong)

In the following type of sentence singular verb is always used:

Each/Every+Singular noun+ and + Singular noun + Singular Verb

Ex. Each pen and pencil is red.

Each/Every+Singular noun + and + Each/Every + Singular noun + Singular Verb

Ex. Each pen and each pencil is red.

Every boy and every girl is laborious.

Every boy and girl is laborious.

If each is used as the subject of sentence then singular verb is used in such sentences.

Ex. Each has a pen.

Note: If each used after plural noun then plural verb is used in such sentences.

Ex. We each have a pen.

We each has a pen. (Wrong)

If the subjects of sentences are Each of/ Either of/ Neither of/ + Plural Noun/ Plural Pronoun, then in such sentences singular verb is used.

Ex. Each of these four pens is red. (Right)

Each of these four pens are red. (Wrong)

Either of those two boys is gentle. (Right)

Either of those two boys are gentle. (Wrong)

If Each/Every/Either/Neither + singular countable noun is used as the subject of the sentence then in such sentence singular verb is used.

Ex. Each boy is handsome. (Right)

Each boy are handsome. (Wrong)

Note: Each, either and neither are Distributive pronouns.

If Each, every, either and neither are used before nouns then they are said distributive adjectives.

Each is used for two or more than two people.

Either is used for two people or thing.

Neither is used for two people or thing.

Every is used for more than two people.

So the point to be noted that for two people we can use only each and for more than two people we can use  either each or every. 

If the pronouns of all the three persons after connecting with and are used as the subject of a sentence then the sequence should be Second person (you), third person (he,she) and then first person (i/we) and in such sentences plural verb should be used.

Ex. You (2nd person), he (3) and i (first person) are good friends. (Right)

You, he and i am good friends. (Wrong)

Note: If the pronouns of all the three persons after connecting with and are used as the subject of a sentence but the sentence expresses some guilty, sin, crime etc. then the sequence should be 123 (first person, second person and third person) and in such sentences plural verbs are used.

Ex. I, you and he are guilty. (Right)

You, he and I are guilty. (Wrong)

If in a sentence Many, a good many, a great many are used as subject of the sentence then in such sentences Plural verbs are used.

Many are absent from the class. (Right)

Many is absent from the class. (Wrong)

If in Many a/ many an + Singular Countable noun is used as the subject of a sentence then in such sentences Singular verbs are used.

Ex. Many a boy goes to college in time. (Right)

Many a boy go to college in time. (Wrong.)

Check your understanding here. (Quiz on these rules,click to take the quiz)