preposition  (noun): a part-of-speech usually coming BEFORE a noun phrase and connecting it to another part of the sentence

preposition  is one of the nine parts of speech.

The name preposition  (pre + position) means "place BEFORE". A preposition  typically comes BEFORE another word—usually a noun phrase. It tells us about the relationship between the noun phrase and another part of the sentence. Some very common prepositions are: in, of, on, for, with, at, by

Look at these example sentences:

  • The book is on  the round table. (relationship in space)
  • We will meet in  November. (relationship in time)
  • I sent the information by  email. (relationship of method)

Several other relationships are expressed by prepositions. In addition, more metaphorical ideas can be expressed such as: in love, beyond doubt, under investigation

If a preposition does not come BEFORE another word, it is still closely linked to another word:

  • Who did you talk to?
  • To whom did you talk?
  • I talked to Jane.

Form

Prepositions have no particular form. The majority of prepositions are single words, but some are two- or three-word phrases:

  • one-word prepositions (before, into, on)
  • complex prepositions (according to, but for, in spite of)
When we say that a preposition comes before a noun phrase, we include:
  • noun phrase (the tall man)
  • noun (rice)
  • pronoun (them)
  • gerund (verb in -ing form: fishing)

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