外交官は、契約条件を受け入れるために頭をうなずいた。

The diplomat nodded his head to accept the terms of the agreement.

彼に考えを変えさせようとする試みは、まるでレンガ壁に頭を打ち付けるようなもので、どんな議論も彼を説得できなかった。

Trying to convince him to change his mind was like banging his head against a brick wall, because no arguments could persuade him.

古いコンピュータの修理がうまくいかなくなると、アニアは別の解決策を探す代わりに、壁に向かって頭を打ち付け始めた。

When attempts to fix the old computer failed, Ania started to hit her head against a wall instead of looking for another solution.