Common nouns are words that refer to general things, people, or places. They are not specific names.
Here are some examples of common nouns:
People:
* teacher
* student
* doctor
* friend
* neighbor
Places:
* school
* park
* city
* country
* restaurant
Things:
* book
* car
* phone
* table
* computer
Let me know if you would like a more specific list of common nouns for a particular category, or if you have any other questions!