A preposition is a word used before a noun or pronoun to indicate direction, time, location, or introduce an object, such as 'in,' 'at,' or 'on.' They can be categorized into prepositions of time, place, agents, and phrase prepositions, each serving different functions in a sentence. Common examples include 'above,' 'below,' and 'across,' which illustrate spatial relationships.

1. WHAT IS A PREPOSITION
A preposition is a word or group of words used before a noun, pronoun, or
noun phrase to show direction, time, place, location, spatial relationships, or to
introduce an object. Some examples of prepositions are words like “in,” “at,”
“on,” “of,” and “to.”
Prepositions tell us where or when something is in relation to something else.
When monsters are approaching, it’s good to have these special words to tell
us where those monsters are. Are they behind us or in front of us? Will they be
arriving in three seconds or at midnight?

2. There are some prepositions which are common in every type of Preposition:
1.)Prepositions of Time:
Prepositions of time show the relationship of time between the nouns to the other parts of a sentence.
On, at, in, from, to, for, since, ago, before, till/until, by.
Example:
~He started working at 10 AM.
~The company called meeting on 25 October
2.)Prepositions of Place and Direction:
Prepositions of place show the relationship of place between the nouns to the other parts of a sentence.
On, at, in, by, from, to, towards, up, down, across, between, among, through, in front of, behind, above, over,
under, below.
Example:
~He is at home.
~He came from England.
TYPE OF PREPOSITION

3. 3.)Prepositions of Agents or Things:
Prepositions of agents or things indicate a casual relationship between
nouns and other parts of the sentence.
“Of, for, by, with, about, etc.”
Example:
~This article is about smartphones.
~Most of the guests have already left.
~I will always be here for you.
4.)Phrase Prepositions:
A phrase preposition is not a prepositional phrase, but they are a
combination of two or more words which functions as a preposition.
Along with, apart from, because of, by means of, according to, in front of,
contrary to, etc.
Example:
~They along with their children went to Atlanta.
~According to the new rules, you are not right.
Here are some of the most
common prepositions:
above
below
after
at
for
into, etc.

4. POSITION OF PREPOSITION
Preposition Example Sentence:
*above
~The red ball is above the blue box.
*across
~The red bar is lying across the blue boxes.
*below
~The red ball is below the blue box.
*on
~The red ball is on the blue box.
*under
~The red ball is under the blue box.