Example sentences from the web:

• ON TIME
  – Today’s flight is on time. Departure is 10:30 am. (=the flight will leave on time, it’s on schedule to leave at 10:30 am)
  – Remember to be on time for work tomorrow or I will fire you! (=do not be late)
  – He starts a new job at the railway station tomorrow and he wants to be on time for work. (= he doesn’t want to be late)
  
• IN TIME
  – Will you be home in time for lunch? (= soon enough for lunch)
  – He was just in time for the last train. (= he was almost too late)
  – The plot to assassinate the president was discovered just in time. (= they could find the hit man before it was too late, otherwise, the president would have been murdered)

Video on this topic:

Now you are ready to test your knowledge on this topic :-).

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