Prepositions of Time: at, in, on We use: at for a PRECISE TIME i n for MONTHS, YEARS, CENTURIES and LONG PERIODS on for DAYS and DATES Look at these examples : I have a meeting at 9am. The shop closes at midnight. Jane went home at lunchtime. In England, it often snows in December. Do you think we will go to Jupiter in the future? There should be a lot of progress in the next century. Do you work on Mondays? Her birthday is on 20 November. Where will you be on New Year's Da y?