What is The ?
The is ; before a vowel article 1. meaning something in particular, as opposed to ‘a’ Where’s the book you brought back from the library? That’s the cat from next door. The town centre has been made into a pedestrian zone. 2. used with something of which only one exists, in particular in geographical names an expedition to the Antarctic A spacecraft landed on the moon. The sun came up over the hills. 3. meaning a group of people or a thing in general, such as dates There’s nothing interesting on the television tonight. She refuses to use the telephone. The streets are crowded at lunchtime. Many people were out of work during the 1990s. Both sisters play the flute. born on the 31st of January 4. meaning something special such as a date It’s the shop for men’s clothes. She’s the doctor for children’s diseases. That’s not the Charlie Chaplin, is it? 5. used to compare The more he eats the thinner he seems to get. The sooner you do it the better. This is by far the shortest way to London. She’s the tallest person in the office. 6. showing quantity or speed We sell tomatoes by the kilo.
source: Easier English, Student Dictionary Upper Intermediate Level