Prepositions of time: 'at'

Grammar explanation

We use the prepositions in, on or at to say when something happens.

at

We usually use at with clock times and mealtimes.

I get up at 6.30 a.m. and go for a run.
She doesn't like to leave the office at lunchtime.

We also use at with some specific phrases such as at the weekend and at night.

At the weekend, I can spend the days how I like.

We can also say on weekends or on the weekend. This is more common in American English.

We say at night when we mean all of the night. But we say in the night when we want to talk about a specific time during the night.

She's a nurse and she works at night.
The baby often wakes up in the night.

We use at with Christmas and other holidays that last several days.

The weather is very cold here at Christmas.
At Chinese New Year, many people go home to their families.