Clause types are categorized into two main groups: independent clauses and dependent clauses. An independent clause can stand alone as a complete sentence because it expresses a complete thought. For example, "She enjoys reading" is an independent clause. On the other hand, a dependent clause cannot stand alone and relies on an independent clause to provide context. It often begins with a subordinating conjunction, such as because, although, or if. An example of a dependent clause is "because she enjoys reading," which needs an independent clause to form a complete sentence, like "She stays up late because she enjoys reading."