This exercise on clauses, I hope will help many a student who finds it difficult to distinguish between the different types of clauses and its usage, to be able to do so with ease.

Clauses:  Definition and Types
Description: This site defines what a clause is, dividing it into Main and Subordinate clauses. It then gives the different types of subordinate clauses: adverb clause, adjective clause, and noun clause, giving the functions of each of these clauses with examples.

Clauses:  Building Clauses

Description: This site defines what a clause is and also gives the difference between a clause and a phrase. It also helps to recognize and to use different types of clauses.

Clauses: The essential building blocks
Description: This site defines a clause and distinguishes a phrase from a clause. It categorizes clauses into independent clauses with examples. It again classifies clauses into restrictive and nonrestrictive clauses. It also defines a relative clause and gives examples of it. It gives a quiz on independent clauses.
 

 Clauses: Notes and Exercises
Description: This site gives notes and exercises on clauses. It is like a dictionary of clauses. It gives a step-by-step explanations and exercises on the various types of clauses.

Easy and Advanced Level of clauses

Description: This site is divided into easy level for all students and advanced level. The easy level deals with different forms of time clauses and advanced level deals with conditional, noun, adjective and adverb clauses with practice quiz and games.