1. Off and on 断断续续
The idea of being a writer bad come to me off and on since childhood, but it wasn't until recently that the possibility took hold.
从孩提时代，我就断断续续地有当作家的念头，但直到最近，这一想法才有了实现的可能。
释义：据说源于早期铁路故障。那时铁路脱轨（off the track）是常有的事，只要扳正（on the track）就行了。
链接：
断断续续，时断时续：
on and off
off again, on again
on again, off again
2. Off the hook 逃脱，溜掉，不受罚
I'll let you off the hook this time, but don't do that again.
这次不罚你，下次不要这样做了。
释义：
hook: 能把人吊死的钩子
off the hook：从钩子上放下来，放一马。
