in time与on time这两个词组都可表示“按时”。
in time : 表示及时。指没有迟到，时间还充裕。
- I got home just in time - it's starting to rain.
我正好及时赶到家——随后就开始下雨了。 - If we don't hurry up, we won't be in time to catch the train.
如果我们不赶快，就不能及时赶上火车了。 - We got there in plenty of time (= we arrived early) for the beginning of the game.
我们比赛前早早地就到了。
on time : 表示准时，按时。指按规定的时刻，不早不晚。
- My parents go to the house right on time.
我父母极为准时地到家。 - The train arrived right on time (= at exactly the correct time) .
火车准点到达。
