Page 223 - Advanced English Grammar in Use

A t , i n a n d o n : p r e p o s i t i o n s o f t i m e

We use at with points of time or periods of time that we think of as points. We use at:
• with exact points of time:
• at midday at midnight at 3 o'clock at 8.15
• with short holiday periods, such as Christmas, Easter, the weekend, etc.:
• I'll see you at Easter. • We often go walking at the weekend.
(In US and Australian English, 'on the weekend' is used, and this is now heard in informal
British English, too.)
• with other short periods that we think of as points, such as the end of January, the beginning of
the year, etc.:
• I get paid at the end of the month.
• with mealtimes, such as breakfast, lunch, dinner, etc.:
• That morning at breakfast, my brother told us he was getting married.
• with night when we mean 'when it is night' or 'each night':
• People can't go out on the streets at night any more, it's so dangerous.
But notice that we use in with the middle of..., and that when we talk about a particular night
we use in the night:
• It's Ann's birthday some time in the middle of May, I think.
• I felt very restless in the night and had to take a sleeping tablet.
• in the phrase at the moment (= now); but notice that we say in a moment (= in a short period of
time):
• John's in Korea at the moment. • I'll be with you in a moment.

B We use in:
• when we talk about longer periods of time such as seasons (e.g. the spring), months, years,
decades (e.g. the 1990's (or the 1990s)), centuries (e.g. the 16th century), and other periods
such as the week before Easter, the hours before the exam, etc.:
) • In the winter you can only use the road with a four-wheel drive vehicle.
• • In the days that followed her operation, she spent a lot of time in bed.
• when we talk about how long it will be before something happens:
• In a few minutes we will be arriving at Delhi Airport, (or, more formally, 'Within...')
• when we say how long something takes:
• He learnt how to program the computer in just a matter of weeks. (= a few weeks)
• with parts of the day, such as the morning, the evening, etc. (see A for 'night'):
• Temperatures today should reach 25°C in the afternoon.
(We can often use during instead of in when we talk about periods of time. See Unit 108.)

We use on when we talk about a particular day, date, or part of a particular day:
• We're meeting again on Friday. • It's her birthday on the 21st.
• I get paid on the last day of the month. • We went to a party on Easter Sunday.
• I've got a meeting on Monday morning.

We rarely use at, in or on before the words all, any, each, every, last, next, one, some, this, or
that when these are followed by a time expression. Compare:
• I'll do it in the morning, and • He hasn't been here all morning, (not ...in all morning.)
• I'll see you again on Friday, and • I'm going to Oslo next Friday, (not ...on next Friday.)
We don't use at, in or on before (the day after) tomorrow and (the day before) yesterday:
• The weather was beautiful yesterday, (not ...on yesterday.)
We prefer What time...? rather than At what time...? except in very formal English.
At, in, on: place => IH'llII'Ll