Blithering idiot
01
完全なばか, とんま
a person who is extremely foolish or incompetent
Informal
例
After forgetting his keys for the third time this week, his frustrated roommate called him a blithering idiot.
今週3回目に鍵を忘れた後、彼のイライラしたルームメイトは彼を完全なばか者と呼んだ。
The teacher struggled to maintain patience with the blithering idiot who could n't grasp even the simplest concepts.
教師は、最も単純な概念さえ理解できないくだらない馬鹿に対して忍耐力を保つのに苦労しました。
