Use of the article 'the'

Use  of the article 'the

The is used before

 1)The names of unique objects
   
    The Taj Mahal,The great wall of China,The Sun etc.

 2) Directions

     The East,the west,the north,the south,the north-east,the north-west,the south-east,the south-west

3)Geographical phenomena

   The Ganga,the Indian ocean,the Bay of Bengal, the Red Sea,the Arabian sea,the Thar desert,the Andaman and Nicobar etc.

4)Group of nations

 The USA,the UK,The UAE,the USSR,the SAARC, The BRITAIN,the BRICS

5)Nationalities

The Indian,the American,the Russian,The Japanese,the Chinese,the Palestinian,the Pakistani,the Bangladeshi etc.

 6) Musical instruments

The piano,the drum,the pipes,the bell,the horn,the bagpipes,the clarinet,the violin etc.

7) superlatives

The best,the most,the highest,the tallest,the largest,the thinnest etc.

8)ordinal numbers

The first,the second,the third,the fourth,the hundredth,the thousandth etc.

9)Holy books

The Gita,the Quran,the Bible,the Vedas,the Puranas,the Iliad etc.

10) when we speak of a particular person or thing or one already referred to

I saw a boy.The boy was tallest.

11) When singular noun represents whole class

I) The cow is useful animal.
ii)The Banyan is kind of a fig tree.

12)Adverbs with comparatives

The more you get,the more they want.