​A clause is component of a (complex) sentence, with its own and predicate, especially on doing the work of a noun, adjective or adverb (Hornby, 1987 : 204). Another definition of clause is a group of words which has its own subject and predicate (Syah, 1977 : 88).

1.     Independent /principal /main clause​

​ Main clause is a clause which contains a complex idea and it can stand by itself as a complete simple sentence (Husain, 1977 : 88)

​2. Dependent/Suordinate Clause

​ Dependent clause is a clause that can’t stand by itself or still depends on independent clause because it does not have a complete idea yet (Husain, 1993 : 90).