get something off your chest
US /ɡɛt ˈsʌmθɪŋ ɔf jʊər tʃɛst/
UK /ɡɛt ˈsʌmθɪŋ ɔf jʊər tʃɛst/

1.
一吐为快, 倾吐心事
to tell someone about something that has been worrying you or making you feel guilty for a long time
:
•
I need to get something off my chest and tell you what's been bothering me.
我需要一吐为快,告诉你困扰我的事情。
•
After he confessed, he felt like he had finally gotten it off his chest.
他坦白后,感觉终于如释重负。