A clause is a group of words that at least have a subject and a verb, and that may be independent (It can stand by itself) or independent (It cannot stand by itself because it does not have full meaning). Dependent clauses may have one of the following three grammatical functions: Adjective, adverb, or noun.
Noun clause: It acts as a noun in a sentence, and they tend to be introduced by words like <em>how, that, what, whatever, when, where, whether, which, whichever, who, whoever, whom, whomever,</em> and <em>why</em>. For example: <u><em>Whatever you tell me</em></u><em> shall remain our secret.</em><em> </em>
Adverb clause: It modifies adjectives, verbs or other adverbs. This type of clauses often answers questions such as <em>why, how, when, where </em>or<em> in what circumstances. </em>For example: <u><em>After drinking that much liquor</em></u><em>, I felt sick.</em><em> </em>(When did you feel sick? A: After drinking that much liquor.
Adjective clause: It modifies a noun, by describing or giving extra information about that noun. It often answers questions like <em>who </em>or <em>which one</em>. For example: <em>Stefano reached out for the cup of coffee </em><u><em>that laid on the window sill.</em></u> (Which cup of coffee? The one that laid on the window sill).