start with a clean slate 改过自新，重新开始

这个表达中的单词“slate”的意思是“石板”。在维多利亚时代，由于能方便地随时擦净重写，孩子们多在深色石板上练习写字，而不是纸张。那时，许多小商铺也是用石板给顾客记账的，月底结算后，重新开始计算。因此，成语“start with a clean slate”的含义就由此而来：“不计过去，重新开始”。

例句

Jack got into a lot of trouble at school last year, but with a new school year and a new teacher, he's starting with a clean slate.

杰克去年在学校里闯了不少祸，但现在新学年，新老师，他可以改过自新，重新开始。

In the last few months I've developed some bad habits, but for the new year I'm going to start with a clean slate.

过去几个月里我养成了一些坏习惯。但在新的一年里，我下决心要洗心革面，重新开始。

George and I sat down and agreed that what's happened in the past is in the past, but now we shall start with a clean slate.

乔治和我坐下来，达成了共识。我们要既往不咎，重新开始。