Level: elementary

We use phrases with prepositions as time adverbials:

  • We use at with:
clock times: at seven o'clock at nine thirty at fifteen hundred hours  
mealtimes: at breakfast at lunchtime at teatime  
these phrases: at night at the weekend at Christmas at Easter
  • We use in with:
seasons of the year: in (the) spring/summer/autumn/winter        
years, centuries, decades: in 2009 in 1998 in the 20th century in the 60s in the 1980s
months: in January/February/March etc.        
parts of the day: in the morning in the afternoon in the evening    
  • We use on with:
days: on Monday/Tuesday/Wednesday etc. on Christmas day on my birthday
dates: on the thirty-first of July on June the fifteenth    
Be careful!

We say at night when we are talking about all of the night:

When there is no moon, it is very dark at night.
He sleeps during the day and works at night.

but we say in the night when we are talking about a specific time during the night:

He woke up twice in the night.
I heard a funny noise in the night.

We often use a noun phrase as a time adverbial:

yesterday today tomorrow
last week/month/year this week/month/year next week/month/year
last Saturday this Tuesday next Friday
the day before yesterday   the day after tomorrow
one day/week/month    
the other day/week/month    

We can put time phrases together:

We will meet next week at six o'clock on Monday.
I heard a funny noise at about eleven o'clock last night.
It happened last week at seven o'clock on Monday night.

We use ago with the past simple to say how long before the time of speaking something happened:

I saw Jim about three weeks ago.
We arrived a few minutes ago.

We use in with a future form to say how long after the time of speaking something will happen:

I'll see you in a month.
Our train's leaving in five minutes.

When (time and dates)



Dear Sir,
thanks for the advice.

Dear teacher,

If I use "on last Sunday", is that correct?

Thanks and regards

Hello akhilsvazhayil,

When we have a time expression with 'last' or 'next' we don't use a preposition. For example:

I saw him last weekend.

I'm going to Spain next year.

I hope that clarifies it for you.

Best wishes,


The LearnEnglish Team

Hi! Is it correct to say "My first lesson on Monday is at ten o'clock."? or must we say "On Monday my first lesson is at ten o'clock."?

Hi Maggie,

Both of those are fine.

Best wishes,



The LearnEnglish Team

Dear teacher,
I would like to know whether time expression in this sentence is correct or not.
On 20/12/2014-03:40pm,the machine was shut down.

Is "at" necessary to tell the exact time?

Best regards,

Hello ohnmaraung,

What you wrote is perfectly comprehensible and you could probably find instances where a date and time is written in this way. As you suggest, however, it might be a bit clearer if you said 'On (date) at (time),...', especially if this is meant to be spoken at some point.

Best regards,
The LearnEnglish Team

Which one is right?
1. on 30/12/2014
2. in 30/12/2014


Hello Nsgb,

The correct preposition here is on. We use 'in' with years and months ('in 1945', 'in March') and 'on' with dates and days ('on 26/08/2014', 'on Wednesday').

Best wishes,



The LearnEnglish Team

Dear teacher,

Is the first sentence is better than the second one ?
We are going to meet next week at six o’clock on Monday.
We will meet next week at six o’clock on Monday.

Thank you !