An ELT Notebook : Prepositions / Prepositional Phrases / Prepositional complement / Prepositional Object
1. A preposition is a word class which, as its name suggests, cannot stand alone. It occurs in "pre-position" to some other item which acts as prepositional complement (also called prepositional object) and completes the prepositional phrase.
Prepositional complements may be any of the following (preposition in bold, complement underlined):
a) A Noun Phrase
We're going on Tuesday, probably in the afternoon.
Stop looking at me like that!
b) A V-ing clause
I found out by googling it.
c) A wh- clause
We were astonished by what we saw
We watched from above.
I can't do it by then.
In some constructions the prepositional complement may occur earlier in the sentence, but can always be retrieved. Eg :
That's the book I was looking for = I was looking for the book.
2. Prepositions may be simple - ie composed of one word (at, by, on, over, with, despite etc) or complex - ie composed of more than one word (in spite of, away from, because of). As these three examples show, complex prepositions generally fall into one of three categories :
a) Preposition + noun phrase + preposition : as a result of, in view of, in line with etc
b) Adverb + preposition : apart from, out of, as for etc
c) Verb or adjective or conjunction + preposition : regardless of, owing to, because of etc
3. Prepositions may also be correlative - ie composed of two parts. For example from/to, between/and
Quirk et al, (1985) A Grammar of Contemporary English. Longman Chapter 6
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