Clause is A major unit of grammar, it may contain: subject, verb phrase object, complement and adverbial.

An independent clause functions on its own to make a meaningful sentence and looks much like a regular sentence

A dependent clause cannot function on its own because it leaves an idea or thought unfinished. It is also called subordinate clause. Dependent clauses help the independent clauses complete the sentence.It can be:

       A noun clause:it contains a subject and a verb;and beginswith that, a question word, whether or if a question word followed by infinitive

       An adjective clause: modifies a noun; it describes, identifies or givesfurther information about it.

       An adverbial clause is a group of words that plays the role of an adverb.