This document discusses the use of common prepositions of place and time in English. For place, "in" is used for names of towns, cities, provinces and countries. "At" is used for addresses and named buildings and places. "On" is used for street, road, avenue or island names. For time, "in" is used for months, "on" is used for days, and "for" is used to indicate a period of time in hours, minutes or seconds. Examples are provided for each case.