We will study in a subsequent lesson the use of noun clauses introduced by relative pronouns. In this lesson we are studying the conjunctions.

In the last sentence, I know where it is, the noun clause where it is, is the object of the verb know, and is introduced by the conjunction where.

363. Noun clauses are introduced by the subordinate conjunctions, where, when, whence, whither, whether, how, why, and also by the subordinate conjunction that. For example:

In all of these examples the noun clauses are used as the objects of the verb. Noun clauses may also be used as objects of prepositions. As, for example:

364. Noun clauses may also be used as the subject of a sentence. As for example:

In all of these sentences, the noun clause is used as the subject of the verb. You will note that most frequently the noun clause used as subject of the verb is introduced by the subordinate conjunction that. But quite often we write these sentences in a somewhat different way. For example: