Has a subject and verb.

Can stand alone as a sentence.

A suburdinate clause that modifies a noun or apronoun.

Use relative pronouns such as: who, whom,whose, that, and which.

Relative pronoun may be dropped at thebeginning of an adjective clause.

An adjective clause is sometimes needed tomake the meaning of a sentence clear. That iscalled an essential clause.

A nonessential clause is when an adjective isnot absolutely needed in order to expressthe complete meaning of a sentence.

The relative pronoun that usually introduces anessential; the relative pronoun whichintroduces a nonessential clause.

A noun clause is a subordinate clause used as anoun.

Words that can be used: how, that, what,whatever, when, where, which, whichever, who,whom, whoever, whose, and why.

Cannot stand alone as a sentence.

Has a subject and a predicate.

An adverb clause is a subordinate clause thatmodifies a verb, an adjective or an adverb.

It tells when, where, how, why, to what extent,or under what condition.

An adverb can come either before a main clauseor after it.

Sometimes words may be left out to avoidrepetition and awkwardness.