Prepositions of Time

We use in for non-specific times during a day, a month, a season, year or when showing duration.For example: I started this website in 1999.She woke up in the night. I was born in September.School starts in two weeks.

We use at for specific times (part or time of day, celebrations, fixed phrases).For example:I start work at 7.00 a.m. I got many presents at Christmas.I arrived at the same time as my sister.I have lunch at 12 o'clock.

We use on for specific days and dates. For example: We're having a party on Tuesday I am leaving the country on the 7th of March.We also use on for some special days. For example: We ate eggs on Easter Sunday.I got many presents on my birthday.

since■ from a certain point of time (past till now)since 1980to ■ telling the time ten to six (5:50) past ■ telling the time ten past six (6:10) till / until ■ in the sense of how long something is going to last He is on holiday until Friday.

by ■ in the sense of at the latest up to a certain time I will be back by 6 o’clock.By 11 o'clock, I had read five pages.for ■ over a certain period of time (past till now) for 2 yearsago ■ a certain time in the past 2 years agobefore ■ earlier than a certain point of time before 2004