In a sentence, noun clauses act as subjects, direct objects, indirect objects, predicate nominatives, or objects of a preposition.
12 "that the defendant was innocent"
The clause is acting as a direct object, so it is a noun clause.
13 "What you have to do"
The clause is acting as a subject, so it is a noun clause.
"find the most efficient way to solve the problem"
The clause is acting as a predicate nominative, so it is a noun clause.
14 "why he wanted to leave the family farm and move to the big city"
The clause is acting as a direct object, so it is a noun clause.
15 "Whoever solves the difficult problem facing the family"
The clause is acting as a subject, so it is a noun clause.
