What's a noun?
(Irregular plural forms of count nouns)
Here are some good sites comparing count and non-count nouns:
Here's a Canadian site from the University of Victoria, BC:
This is an American site that features video lessons. After you look at this lesson, go to the Home Page of the site. Many other grammar lessons are available.
(This is the Home Page:)
Here are some quizzes that you can do to check your understanding the difference between count and non-count nouns: