Why is this important? Why do some nouns have no plural?

English nouns are often described as "countable" or "uncountable".

In this lesson we look at:

Countable nouns are easy to recognize. They are things that we can count. For example: "pen". We can count pens. We can have one, two, three or more pens. Here are some more countable nouns:

• dog, cat, animal, man, person

• bottle, box, litre

• coin, note, dollar

• cup, plate, fork

• table, chair, suitcase, bag

Countable nouns can be singular or plural:

• My dog is playing.

• My dogs are hungry.

We can use the indefinite article a/an with countable nouns:

• A dog is an animal.

When a countable noun is singular, we must use a word like a/the/my/this with it:

• I want an orange. (not I want orange.)

• Where is my bottle? (not Where is bottle?)

When a countable noun is plural, we can use it alone:

• I like oranges.

• Bottles can break.

We can use some and any with countable nouns:

• I've got some dollars.

• Have you got any pens?

We can use a few and many with countable nouns:

• I've got a few dollars.

• I haven't got many pens.

Uncountable Nouns

Uncountable nouns are substances, concepts etc that we cannot divide into separate elements. We cannot "count" them. For example, we cannot count "milk". We can count "bottles of milk" or "litres of milk", but we cannot count "milk" itself. Here are some more uncountable nouns:

• music, art, love, happiness

• advice, information, news

• furniture, luggage

• rice, sugar, butter, water

• electricity, gas, power

• money, currency

We usually treat uncountable nouns as singular. We use a singular verb. For example:

• This news is very important.

• Your luggage looks heavy.

We do not usually use the indefinite article a/an with uncountable nouns. We cannot say "an information" or "a music". But we can say a something of:

• a piece of news

• a bottle of water

• a grain of rice

We can use some and any with uncountable nouns:

• I've got some money.

• Have you got any rice?

We can use a little and much with uncountable nouns:

• I've got a little money.

• I haven't got much rice.

Countable/Uncountable Nouns

Sometimes, the same noun can be countable and uncountable, often with a change of meaning.

Do we say "Atlantic Ocean" or "the Atlantic Ocean"? Should I write "february" or "February"?

Names (Proper Nouns)

A name is the special word we use for a person, place or organization, like John, Marie, London, France or Sony. A name is a noun, but a very special noun. It is called a "proper noun" and has special rules.

Using Capital Letters with Names

We always use a Capital Letter for the first letter of a name. This includes names of people, places, companies, days of the week and months. For example:

• They like John. (not *They like john.)

• I live in England.

• She works for Sony.

• The last day in January is a Monday.

• We saw Titanic in the Odeon Cinema.

Names Without "the"

We do not use “the” with names of people. For example:

Names With "the"

We normally use "the" for country names that include “States”, “Kingdom”, “Republic” etc:

We normally use “the” for names of canals, rivers, seas and oceans:

We normally use “the” for plural names of people and places:

Look at these sentences:

• I saw the Clintons today. It was Bill’s birthday.

• Trinidad is the largest island in the West Indies.

• Mount Everest is in the Himalayas.

We normally use “the” with the following sorts of names:

We normally use “the” for names made with “…of…”:

• the Tower of London

• the Gulf of Siam

• the Tropic of Cancer

• the London School of Economics

• the Bank of France

• the Statue of Liberty

 source: http://www.englishclub.net/grammar/nouns/names.htm