on time & in time
on time：按时 ，准时 The bus came right on time. 公共汽车正好准时到达。 The work was finished on time and within budget.工作按时完成且未超出预算。 They are unlikely to get here on time, I fear.恐怕他们不大可能准时到达这
some time，some times 和 sometimes
口诀是分开是一段，相连为某时。分开s是倍，次，相连s是有时。 具体区分 1. sometime 表示某个时候，可以是过去也可以是将来。I will tell you this secret sometime in the future。 2. sometimes 表示有时候，相当
it's time (for sb.) to do sth.
it’s time (for sb.) to do sth：到了某人该做某事的时候了。 It’s time for us to go to school. = It’s time for school. It’s time to go to bed. = It’s time for bed.
