(as) dead as a doornail
US /əz dɛd əz ə ˈdɔrˌneɪl/
UK /əz dɛd əz ə ˈdɔrˌneɪl/

1.
彻底报废, 死透了
completely dead; no longer alive or functioning
:
•
The old car was as dead as a doornail after the accident.
那辆旧车在事故后彻底报废了。
•
I tried to revive the computer, but it was as dead as a doornail.
我试图重启电脑,但它彻底坏了。