draw a line under something
US /drɔː ə laɪn ˈʌndər ˈsʌmθɪŋ/
UK /drɔː ə laɪn ˈʌndər ˈsʌmθɪŋ/

1.
画上句号, 一笔勾销
to consider something to be finished and to not think about it or discuss it anymore
:
•
It's time to draw a line under the argument and move on.
是时候为这场争论画上句号,继续前进了。
•
Let's just draw a line under what happened and start fresh.
我们把发生的事情一笔勾销,重新开始吧。