Final answer:
Sentences with adjective or adverb clauses are usually complex sentences. This is because both types of clauses act as subordinate clauses adding extra information to the main clause, making the sentence complex.
Step-by-step explanation:
Sentences that contain adjective or adverb clauses are usually complex sentences. This is due to the fact that both adjective and adverb clauses function as subordinate clauses which, when integrated into a sentence, creates a complex sentence.
A complex sentence contains a main clause (also known as an independent clause) and one or more dependent clauses (also known as subordinate clauses). These dependent clauses can begin with relative pronouns (which, who, that, etc.) to form adjective clauses or subordinating conjunctions (because, although, since, etc.) to form adverb clauses. These clauses add extra information to the main clause, making the overall sentence complex.
For instance, consider the sentence, 'The book that you recommended is very engaging.' The main clause here is 'The book is very engaging', which can stand alone as a meaningful sentence. 'That you recommended' serves as the adjective clause, further describing the noun book.
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