add insult to injury

hit someone when he is already down, hurt someone even more than he is already hurt

made a hurtful situation even worse, hurt someone even more than he has been hurt already

To add insult to injury is a phrase meaning to compound a problem (or set of problems) with further a problem or problems. Add Insult to Injury is the fourth album by British electronic musicians Add N to (X). It was released on October 16, 2000 by Mute Records. The album is essentially two mini-albums fused together, as half was written and performed by Ann Shenton and Steve Claydon, while the other half was written and performed by Barry 7, with occasional help from Dean Honer from The All Seeing I.
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add another negative, make it worse, put your foot in it If you say his answer is wrong, and then say he can't understand, you've added insult to injury.

AGGIUNGERE L'OFFESA AL DANNO. AGGIUNGERE LA BEFFA AL DANNO

idm. ทำให้เลวร้ายขึ้น (โดยเฉพาะทำให้เศร้าเสียใจ, ทำให้อันตรายมากขึ้น)