The beginning and the ending of a sentence are its most emphatic positions. Coordination is used for ideas that are equally important. Subordination is used for ideas of lesser importance. A clause is a group of related words containing a subject and a predicate. It can be either independent or dependent.
Adjective clauses modify nouns, pronouns or groups of words used as nouns.
They are introduced by relative pronouns or subordinating conjunctions. Nonessential or nonrestrictive clauses are set off by commas. An adverb clause, like an adjective clause, is a group of related words containing a subject and a predicate. An adverb clause can be either main or subordinate. An adverb clause modifies verbs, adjectives, other adverbs, other clauses or whole sentences.