ばかのひとつおぼえ

馬鹿の一つ覚え

表記・読み：バカの一つ覚え・バカのひとつ覚え・ばかの一つ覚え・ばかのひとつ覚え・ばかのひとつおぼえ

1. 1

   one who knows little often repeats it; a fool's one bit of knowledge

   expressions (phrases, clauses, etc.)proverb