Noun clauses in English grammar are subordinate clauses that consist of a subordinating conjunction followed by a clause. Noun clauses perform nominal grammatical functions.
Noun clause is a grammatical form.
The nine grammatical functions performed by noun clauses are subject, subject complement, direct object, object complement, indirect object, prepositional complement, adjective phrase complement, noun phrase complement, and appositive.
The subordinating conjunctions in English that introduce noun clauses are that, Ø, if, whether, wh– words, and wh-ever words.
Noun clauses may be either finite or nonfinite. Finite noun clauses contain conjugated verbs functioning as predicates. Nonfinite noun clauses contain unconjugated verbs functioning as predicates.
Noun clauses may be formed from declarative or interrogative sentences.
DeCarrico, Jeanette S. 2000. The structure of English: Studies in form and function for language teaching. Ann Arbor, MI: The University of Michigan Press.
Hopper, Paul J. 1999. A short course in grammar. New York: W. W. Norton & Company.
Huddleston, Rodney. 1984. Introduction to the grammar of English. Cambridge: Cambridge University Press.