OTHER USES OF "THE"

Main points

You do not normally use `the' with proper nouns referring to people.
You do use `the' with many proper nouns referring to geographical places.
You use `the' with some adjectives to talk about groups of people.

You do not normally use `the' with proper nouns that are people's names.

However, if you are talking about a family, you can say `the Browns'.

You use `the' with some titles, such as `the Queen of England', and with the names of some organizations, buildings, newspapers, and works of art.
...the United Nations...
...the Taj Mahal...
...the Times...
...the Mona Lisa.

You do use `the' with some proper nouns referring to geographical places.
...the Bay of Biscay...
...the Suez Canal.
...the Arabian Gulf...
...the Pacific Ocean.

You use `the' with countries whose names include words such as `kingdom', `republic', `states', or `union'.
...the United Kingdom...
...the Soviet Union.

You use `the' with countries that have plural nouns as their names.
...the Netherlands...
...the Philippines.

Note that you do not use `the' with countries that have singular nouns as their names, such as `China', `Italy', or `Turkey'.

You use `the' with names of mountain ranges and groups of islands.
...the Alps...
...the Himalayas.
...the Bahamas...
...the Canaries.

Note that you do not use `the' with the names of individual mountains such as `Everest' or `Etna', or the names of individual islands such as `Sicily', `Minorca', or `Bali'. You use `the' with regions of the world, or regions of a country that include `north', `south', `east', or `west'.
...the Middle East...
...the Far East.
...the north of England...
...the west of Ireland.

Note that there are some exceptions.
...North America...
...South-East Asia.

You do not use `the' with `northern', `southern', `eastern', or `western' and a singular name. ...northern England...
...western Africa.

You use `the' with the names of areas of water such as seas, oceans, rivers, canals, gulfs, and straits.
...the Mediterranean Sea...
...the Atlantic Ocean.
...the river Ganges...
...the Panama Canal.
...the Gulf of Mexico...
...the straits of Gibraltar.

Note that you do not use `the' with lakes.
...Lake Geneva...
...Lake Superior.

Note that you do not use `the' with continents, cities, streets, or addresses.
...Asia...
...Tokyo.
...Oxford Street...
...15 Park Street.

You use `the' with adjectives such as `rich', `poor', `young', `old', and `unemployed' to talk about a general group of people.
You do not need a noun.
Only the rich could afford his firm's products.
They were discussing the problem of the unemployed.

When you use `the' with an adjective as the subject of a verb, you use a plural verb.
In the cities the poor are as badly off as they were in the villages.

You use `the' with some nationality adjectives to talk about the people who live in a country.
They will be increasingly dependent on the support of the French.
The Spanish claimed that the money had not been paid.

With other nationalities, you use a plural noun.
...Germans...
...the Americans.
When you use `the' with a nationality adjective as the subject of a verb, you use a plural verb. The British are worried.

You use `the' with superlatives.
He was the cleverest man I ever knew.
He was the youngest.
His shoulders hurt the worst.
It was the most exciting summer of their lives.