A Preposition is the word or group of words that is generally placed before a noun or a pronoun to express its relation with other part of the sentence. The noun or pronoun used with the preposition is called its object.
Consider the following Examples
I am coming from Delhi.
Here, we have a noun 'Delhi' and a pronoun 'I'. Preposition is a word that is placed before a noun or pronoun. There is no word before pronoun 'I'. Before Delhi, there is a word 'from'. From is the preposition in this example. 'Delhi' is object of 'from'.
Tom depends on you.
Here, we have a noun Tom and a pronoun you. There is a word before pronoun but there is no word before the noun. Therefore, the preposition in this case is 'on'. 'you' is the object of 'on'.
Some commonly used prepositions -
|Coming from some place||I am coming from the park.|
I am coming from my home.
|Point of Time||I will join from tomorrow.|
His timing starts from 11AM
|From any source||I heard it from Tom.|
I wrote it from the book.
|One body leaving surface of another body||I picked the mobile off the bed.|
I am wiping the dust off the screen.
Monkey jumped off the tree.
Move the cup off the table.