Prepositions of time indicate the period of time that something happens (during, from, since, throughout, until, etc)

• I had a couple of terrifying nightmares during the night.
• She swears never to talk to me again from tomorrow.
• His girlfriend has been missing since last Sunday.
• He slept throughout the lecture.
• They said I was breastfed until the age of six.

Prepositions of time used to indicate a particular time (at, by, in, on, etc)

• I had a big argument with my grandma at lunchtime.
• The funeral should be over by five o’clock.
• The astrologer said I would be dead in five years.
• The boss is always sleepy on Monday mornings.

Prepositions of time used to indicate a particular time in relation to another (after, before, etc)

• I start to wonder whether I will be Heaven or Hell after death.
• I usually need to go to the toilet before having my breakfast.