blot your copybook

US /blɑt yər ˈkɑp.i.bʊk/
UK /blɑt yər ˈkɑp.i.bʊk/
"blot your copybook" picture
1.

mencemarkan reputasi, merosakkan rekod

to do something that spoils your good reputation or record

:
He was a promising student, but he blotted his copybook by cheating on the final exam.
Dia seorang pelajar yang menjanjikan, tetapi dia mencemarkan reputasinya dengan menipu dalam peperiksaan akhir.
One mistake could blot your copybook for years to come.
Satu kesilapan boleh mencemarkan reputasi anda untuk tahun-tahun akan datang.