Sometimes two prepositions can be used with the same noun, but the meaning is different.
- Lessons begin at 8.30 and I always arrive on time. (= at 8.30)
- Lessons begin at 8.30 and I always get there in time. (= before 8.30; I’m not late)
- In the end we went home. (= finally, after a long period)
- At the end of the book they get married.
- The two men are in business. (= they are businessmen)
- The two men are in Germany on business. (= they are there for work and not for a holiday)
- I’ll see you in a moment. (= very soon)
- I can’t speak to you at the moment. (= right now)
On time and in time
On time = punctual, not late.
If something happens on time, it happens at the time which was planned:
- The 11.45 train left on time. (= it left at 11.45)
- Til meet you at 7.30.’ ‘OK, but please be on time.’ (= don’t be late, be there at 7.30
- The conference was well-organised. Everything began and finished on time.
The opposite of on time is late:
- Be on time. Don’t be late.
In time (for something / to do something) = soon enough:
- Will you be home in time for dinner?
(= soon enough for dinner)
- I’ve sent Emma a birthday present. 1 hope it arrives in time (for her birthday).
(= on or before her birthday)
- I’m in a hurry. I want to be home in time to see the game on television.
(= soon enough to see the game)
The opposite of in time is too late:
- I got home too late to see the game on television.
You can say just in time (= almost too late):
- We got to the station just in time for our train.
- A child ran into the road in front of the car – I managed to stop just in time.