Some Quizzes on Adjective Clauses

http://highered.mcgraw-hill.com/sites/0073406414/student_view0/chapter9/parts_1_and_2.html

You should try the first four quizzes.

If these are helpful, please let me know. (If these are helpful--adverb clause of condition)

Also let me know if they're not helpful. (If they're not helpful--noun clause as the object)