ADJECTIVE CLAUSES WITH CONJUNCTIONS

376. The adjective clauses which we have been studying so far have been introduced by relative pronouns. Adjective clauses may also be introduced by conjunctions, such as, where, when, whence, or why. As, for example:

Note in these sentences the clauses, where a terrible battle was fought, when opportunity will be his, why this world-war was precipitated, are all adjective clauses modifying the nouns place, hour and reason, and are introduced by the conjunctions where, when, and why. These are adjective clauses because they modify, by either limiting or describing, the nouns with which they are used. You will note that we could omit the nouns in the first two of these sentences and these clauses would become noun clauses, for they would be used in the place of a noun. As, for example:

377. We determine whether a clause is an adjective or an adverb or a noun clause just as we determine whether a word is an adjective, adverb or noun, by the work which it does in a sentence. Noun clauses are used in the place of a noun; adverb clauses modify verbs, adjectives, and adverbs; adjective clauses modify nouns and pronouns.