2. Articles
Definite articles
THE
Undefinite articles
A / AN
  "I'd like a glass of orange juice, please," John said.     "I put the glass of juice on the counter already," Sheila replied.

3. No article is used before uncountable and plural nouns when used in a general sense. I like music. She’s interested in animals and wants to be a vet.
When there is a following phrase or clause specifying exactly what is being talked about, the definite article is required before uncountable and plural nouns. I like the music they play at the jass club in town. Are the animals in the rainforest safe in their enviroment?

4. A or an is used the first time a singular countable noun is mentioned, but after this, the is used since the reader or listener is clear about what is being referred to. A bird was trapped in the room and Anna called her brother to help her free the poor creature.
Singular countable nouns must always have an article or some other determiner (like each, my, this) except for a few fixed expressions like : By car In hospital …

5. The is not used with te names of most countries
The is not used with te names of most countries. It is, however, used with plural names or names of countries which contain a common noun. The Pilippines The United States
The is used with playing instruments but no article is used with playing games. Mary’s hobby is playing the guitar and mine is playing chess.
Behave like singular nouns with verbs
Behave like singular nouns with verbs: The United States is a huge country

6. The can often be used before car, train, bus, plane, ferry or boat when talking about the use of different types of transport in general, even when the mode of transport has not previously been referred to. A is also used. Are you going to take the train / a train /the bus/ a bus to London tomorrow?
Parts of the body are usually preceded by a possessive pronoun rather than an article when they are talked about in the context of their relation to a specific body or bodies. When parts of the body are talked about in general, the is normally used. Sally has sprained her ankle The liver is the largest organ in the body

7. The word own must be preceded by a possessive pronoun rather than the or a When did you first get your own car?
When we talk about the units in which commodities are generally bought or sold, we often use by + the. When we talk about price, we usually use a / an. Her parents used to buy coal by the ton. Those chocolates are nearly $100 a kilo.
If we miss out a before few and little, the meaning is changed to mean not many / not much She had a few friends (some) She had few friends (less than you expected)

8. We use a /an when describing someone or something in a way that applies to others Kim is an interesting character (there are other interesting characters in the world)
Each and every precede singular nouns. Every girl has her own locker and each class has its own cloakroom

9. Ejercicio 1
Ejercicio 2
Ejercicio 3
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