Singular and plural

1- Expressions of quantities:
The verb agrees with the noun (or pronoun) that 
follows an expression of quantity.

Some of the speech is interesting.
Some of the speeches are interesting.
A lot of the news is good
A lot of my pencils are broken.
The number of cars in the park is twenty. (The number is the subject)
A number of cars are foreign. (A number of is followed by plural noun 
and plural verb)

Expressions of quantity: 
Some of, a lot of, most of, half of, three-quarter of, 
twenty percent of, a number of, etc.

2- Every and Each
 
Every item has been read 
Every item, article and publication has been provided.
Each car and bike in the park is new.
Each of the books costs ten dimes.
One of his friends is teaching physics.
None of the relatives knows her friend.
Everyone (Everybody) is nice.

Every and each require singular verb. Nouns that follow every and each 
are singular. But they are plural after each of and one of.

None of + plural noun + singular verb: very formal
None of + plural noun + plural verb: informal (speech and writing)

3- There is and there are:
 
There is a swallow on the tree.
There are a lot of swallows on the tree.
There are a dime and a dollar that you ask me for. (Formal)
There is a dime and a dollar that you ask me for. (Informal)


5- Some irregularities:
 
Expression of time, money and distance are usually singular.
Three hours of study is not enough.
Fifty dollars for this book was too much to pay.
Seven thousand kilometers is too far to travel.

Nouns ending in -ics take singular verbs when 
they refer to an area of study.

Physics is interesting.
They take plural verbs when they refer to a particular situation.
The Mathematics in this item give wrong results.
Spanish is easy to learn. (Spanish = language)
The Chineese live in Chinatown. (The Chineese: people)
This pattern exists with nouns of nationality that end in -ese, -ch, -sh. 
(French, English,)
Sometimes an adjective is used as a noun. It is preceded by The and refers 
to people that have this quality. The rich = The people who are rich.
When the rich make the war, the poor pass away.

6- Few/a few Little/a little:
 
 Count nouns:
A few = some: positive idea (Something exists, is present)
Few = not many: negative idea (Something is largely absent)

Non count nouns:
A little = some: positive idea
Little = not much: negative idea

Often few and little are preceded by very:
They have very little money and very few friends.

 
7- Nouns as modifiers:
When a noun is used as modifier, it is in its singular form.
The garden has flowers in it. It is a flower garden
The juice has fruit in it. It is fruit juice.

When a noun used as a modifier is combined with a number 
expression, the noun is singular and a hyphen ( - ) is used.

Her car is fourteen years old. She has a fourteen-years-old car.


8- Using Other: 
 He has twelve books:
One, another, another,..., 
others = other ones = other books 

He has two books:
One, the other = the other book ( the rest of a specific group)

He has twelve books:
One - the others = the other books (11 books) ( the rest of a specific group)

Each other = one another : reciprocal relationship

Every other : alternate ( one : yes, second : no, third : yes. Fourth : no, etc)

Another is used with expression of time, money, and distance even if these 
expression contains plural nouns.

He will work there for another five weeks to earn another five hundred dollars. 
But It will take him another ten miles to drive.


9- Collective nouns :
Audience  -  class  - committee  -  couple  - crowd  - faculty  -  family  -  
government  - group  - public  -  staff  -  team.

The public were friendly. They clap their hands. ( Formal)
The public was friendly. They were very happy. 

It was composed of thousands of people. ( informal ) 
( It is used because the collective noun is considered a single 
unit instead of a collection of various individual people).


10- Some irregular noun plurals :

To make the plural form :
If the final -y is preceded by a consonant : change the y to i and add -es:
baby : babies, duty : duties

If the final -y is preceded by a vowel : Add only -s
Toys, monkeys, valleys, days

If a noun ends in -fe or -f the ending is changed to -ves 
Except : beliefs, chiefs, roofs, staffs
Wife : wives, thief : thieves, shelf  : shelves

Add -es to nouns ending in -sh, -ch, -s, -z,  and -x 
Except: monarchs, stomachs
Dish : dishes, class : classes, box : boxes

Add -es to nouns that end in -o 
Except : pianos, zoos, and radios
Tomato : tomatoes, hero : heroes, mosquito : mosquitoes 

Child : children - 
Remember: The child’s book. The children’s books.
But : The boy’s ball. The boys’ balls

Foot : feet, goose : geese, louse : lice, man : men
Woman : women, mouse : mice, ox : oxen, tooth : teeth
Deer : deer, fish : fish, sheep : sheep, species : species,
Means  : means, series : series
One fish is … Two fish are ( no s : fish is uncountable noun)


The final sound in the following plural forms is pronounced like the
Word “sees”:
Analysis : analyses, basis : bases, crisis : crises, thesis : theses, 
hypothesis : hypotheses, parenthesis : parentheses.


Some of the words borrowed or adapted from other languages have
foreign plurals, especially common in field of science
-is : -es , -um : -a , -on : -a, -us : -I , -a : -ae, -ex and -ix : -ices
Datum : data, bacterium ; bacteria, medium : media
Criterion : criteria, phenomenon : phenomena
Stimulus : stimuli , nucleus : nuclei
Radius : radii , formula : formulae ( or formulas) , vertebra : vertebrae, 
vita : vitae, index ( indexes) : indices, appendix ( appendixes) : appendices.


The United States = singular
The news , the fruit = singular
People = plural (peoples = nations or ethnic groups)
Police = plural