Exercises countable and uncountable nouns

http://www.ihbristol.com/free-english-exercises/test/esol-smc-countable-and-uncountable-nouns
http://www.proprofs.com/quiz-school/story.php?title=COUNTABLE-UNCOUNTABLE-NOUNS-IN-ENGLISH-1
http://a4esl.org/q/f/x/xz37mpk.htm
http://perso.wanadoo.es/autoenglish/count.htm
http://speakspeak.com/english-grammar-exercises/intermediate/countable-and-uncountable-nouns