Answer:
Proper nouns: The Ganga, Indians, Captain, Reema, Africa, Sanjay.
Common nouns: herd of cows, field, pile of books, table, creatures, food, magician, keys, pigeon, river, crowds of people, streets, crew, sinking ship, class, monitor, winter, flocks of birds, continent, horse, cart, sand, company, actors, album, CDs, songs, teams, buses, stadium, we, groups of pilgrims, river.
Collective nouns: herd of cows, pile of books, creatures, food, keys, crowds of people, streets, crew, class, flocks of birds, actors, CDs, songs, teams, buses, we, groups of pilgrims.
Explanation: All nouns talk about people, things, animals or places, but they can be classified into different kinds of nouns. The proper nouns are specific and particular, they refer to names and are always on capital letters, such as The Ganga, Reema, Africa. Meanwhile, common nouns refer to a more general context, such as pigeon, pile of birds, herd of cows, etc. Finally, collective nouns are common nouns that compile several nouns of the same type, for instance: herd of cows, crew, class.