Articles

General.	Specific.
Use a or an.	Use the.	We don´t usually use the.		When we use a or an and the.
Jobs: Sally´s an engineer. Javier´s a lawyer.	When the speaker and hearer know the thing we are talking about: Close the door. Open the window.	When we talk about people or thing in general: Men are more interested in sports tan women.		We often use a the first time we mention a person  or thing and then the the next time because it is now clear who or whant we are talking about: Let´s have a pizza. The pizzas are very good here. I live in an apartament. The apartament is small.
In expressions of frecuency: Tree times a week.	When there is only one of something: The sun. The moon.	Before possessive ´s: She´s my mother´s cousin.
Indicate something or someone in singular: I want an orange. She need a chair.	Before superlative adjetives: Asia is the biggest continent. Real Madrid is the best team. The worse		Whit the following: Meals: lunch, dinner, etc. Places: work, school, bed, etc. By+ transport: go by car, travel by plane, etc.