5.94 'in' for specific time

'In' is also used when you want to specify a period of time, minutes, hours, days, and so on, using an ordinal:

• Vehicle sales in the first eight months of the year have plunged by 24.4 per cent.
• ...in the early hours of the morning.

'In' is also used with some other nouns referring to events and periods of time:

• My father was killed in the war.
• Everyone does unusual jobs in wartime.
• In the holidays older children can cook something simple for themselves when they deign to turn up.
• Two people came to check my cabin in my absence.

Ordinals are explained in paragraphs 2.249 to 2.256.