First, to change an adjective into an adjective phrase. As, for example:

Second, to change an adverb into an adverb phrase. As, for example:

Third, to express a meaning which we can express in no other way; as, for example, They are fighting for their country. There is no single word which we can use to express the meaning which we express in the phrase, for their country.

311. So the preposition has given us a new means of expression, the prepositional phrase. We can, by its help, use a phrase in place of an adjective to modify a noun or a pronoun, and in place of an adverb to modify a verb or an adjective. And we can also use the prepositional phrase to express relationship which we cannot express by a single adjective or adverb.

If I want to tell you that I see a bird in yonder tree, such an expression would be impossible without that little preposition in. By the use of various prepositions, I can express to you the relationship between the bird and the tree. I can tell you whether it is under the tree, or in the tree, or over the tree, or flying around the tree, or near the tree. By the use of the various prepositions, I can express accurately the relationship that exists between the bird and the tree.

Exercise 1

Look up the list of prepositions in Section 306, on page 184. Use the following pairs of words in sentences and use as many different prepositions as you can to express the different relationships which may be expressed between these words. For example, take the two words, man and house. You may say: