Prepositions form a small but very important word class. We use prepositions very frequently. In fact, the prepositions to, of, in, for, on, with, at, by, from are all in the top 25 words in English. If you can understand and correctly use prepositions, it will greatly improve your fluency. And remember, there are not very many prepositions. There are only 150 prepositions and we only use about 70 of these commonly. The following rules will help you understand and use prepositions correctly.

1. A preposition must have an object

All prepositions have objects. If a "preposition" does not have an object it is not a preposition‚ÄĒit's probably an adverb. A preposition¬†always¬†has an¬†object. An adverb¬†never¬†has an object. Look at these example sentences:

  • They are¬†in¬†the kitchen.¬†(preposition¬†in¬†has object¬†the kitchen)
    Please come in. (adverb in has no object; it qualifies come)
  • There was a doorway¬†before¬†me.¬†(preposition¬†before¬†has object¬†me)
    I had never seen it before. (adverb before has no object; it qualifies seen)
  • I will call¬†after¬†work.¬†(preposition¬†after¬†has object¬†work)
    He called soon after. (adverb after has no object; it qualifies called)

2. pre-position means place before

The name ‚Äúpreposition‚Ä̬†indicates that a¬†preposition¬†(usually) comes¬†before¬†something (its¬†object):

  • I put it¬†in¬†the box.

But even when a preposition does not come before its object, it is still closely related to its object:

  • Who¬†did you talk¬†to? / I talked¬†to¬†Jane.

3. A pronoun following a preposition should be in object form

Thenounorpronoun that follows a preposition forms a ‚Äėprepositional¬†object‚Äô. If it is a pronoun, it should therefore be in the¬†objective form¬†(me, her, them), not subjective form (I, she, they):

  • This is¬†from¬†my¬†wife¬†and¬†me.
  • That‚Äôs¬†between¬†him¬†and¬†her.
  • Mary gave it¬†to¬†them.

4. Preposition forms

Prepositions have no particular form. The majority of prepositions are one-word prepositions, but some are two- or three-word phrases known as complex-prepositions:

  • one-word prepositions¬†(before, into, on)
  • complex prepositions¬†(according to, but for, in spite of, on account of)

5. to preposition and to infinitive are not the same

Do not confuse the¬†infinitive particle¬†‚Äúto‚ÄĚ (to sing, to live) with the¬†preposition¬†‚Äúto‚ÄĚ (to London, to me).

to as preposition

  • I look forward¬†to¬†lunch
    I look forward to seeing you
    I look forward to see you
  • They are committed¬†to¬†the project.
    They are committed to keeping the price down.
    They are committed to keep the price down.
  • I am used¬†to¬†cars.
    I am used to driving.
    I am used to drive.

to as infinitive particle

  • They used¬†to live¬†in Moscow.
  • They love¬†to sing.

6. The golden preposition rule

A preposition is followed by a "noun". It is NEVER followed by a verb.

sources : Original Link