Идиомы - устойчивые выражения и словосочетания.

make a clean breast of (something) - сознаться в чём-либо, облегчить душу.

I decided to make a clean breast of things and I think I will feel better.

ring a bell - вызвать воспоминания, найти отклик в душе.

The name rings a bell; I may have heard it before, but I can't place it properly.

in black and white - в письменном виде.

Sofia prefers to get the information in black and white before she goes to the job interview.

make a bundle/pile - заработать много денег.

Sam's uncle has made a bundle on the stock market and he is very wealthy now.

ring true - звучать правдиво.

Winters in Europe are becoming milder and milder, so the predictions of the meteorologists seem to ring true.