绞尽脑汁

His classmates were labouring with elementary algebra.

他的同学们正在绞尽脑地演算初等代数题。

He had to rack his brains to solve that complicated problem.

他不得不绞尽脑去解决那复杂题。

I’ve been racking my brains all day trying to remember his name.

我一整天都绞尽脑，回忆起他的字。

We’re all scratching our heads for an answer to the problem.

为了找到题的答案我们都绞尽脑。

He puzzled himself over the matter.

他对那件事绞尽脑。

She is worrying the problem out.

她正在绞尽脑解决题。

All night I have been tossing and turning racking my brains to think what could have possessed the young man to kill himself.

整整一晚我辗转反侧, 绞尽脑, 弄明白是什么原因竟能促成年轻人自杀。