So What is a Preposition? By: Elizabeth Crocker

Prepositions are a group of words that show relationships between nouns, pronouns and other words in a sentence. Most often they come before a noun. They never change their form, regardless of the word they are referring to.

Prepositions can come before a time or place : For example: at 10a.m. at home on Tuesday, December 6th on the table in January in Riyadh

Preposition of Time  English Word  Usage  Example  on  days of the weeks  on Monday  in  months/season  time of day  year  after a period of time (when?)  in August/ in winter  in the morning  in 2009  in an hour  at  for night  a point of time (when?)  at night  at half past nine

Prepositions of Place  English Word  Usage  Example  in  room, building, street, town, country  book, paper  car, taxi  picture, world  in the kitchen, in Riyadh  in the book  in the car, in the taxi  in the picture, in the world  at  meaning next to, by an object  for events  place where you are to do something typical (watch a movie, study, work)  at the door  at a concert, at the party  At the theater, at school, at work  on  Being on a surface  For a certain side (left or right)  for television, radio  on the table, on the wall  on the left  on TV, on the radio