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uI’d like to talk to you today about anexciting development. (Something for the first time).
uClimate protection is a challenge for ourentire society. (One from a group of several).
uEnvisat is a fully-equipped observationsatellite. (Classifying people or things as belonging to a group).
uMy brother is an engineer.(What job somebody does).
The
1. When the listener/reader knows whichthing we mean (it may have been mentioned before) or it is understood whichthing we mean:
e.g.Envisat is a fully-equipped observation satellite… The satellitewas launched in 2002.
As part of the conference onenvironmental awareness …
I went to a conference onenvironmental awareness last week.
2. When there is only one of this thing:
The earth, the sun, the twentiethcentury, the sixties, the government, the prime minister
3. For superlatives
It is equipped with the best eyespossible.
4. To talk about playing a musicalinstrument:
He plays the piano and she playsthe guitar.
5. With certain proper nouns:
Nationalities (the British, the Chinese,the Egyptians)
Rivers (theThames, the Yangtze, theNile)
Island groups (the Maldives, thePhillippines, the Seychelles)
Mountain ranges (the Alps, the Himalayas)
Seas and oceans (the Black Sea, theMediterranean, the Pacific)
Country names that representa group (theUnited Kingdom, the United States of America)
Many famous/historical buildings(the White House)
Noun phrases with of (the Great Wall of China, theTemple of Heaven)
6. University names
the University of Sydney, Macquarie University
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