hard heart的用法和樣例：
例句
- Her hardness of heart disappointed him.
她冷酷的心使他失望。 - The man's hard eyes under the cloth looked at him.
蒙面布下面那人冷酷的雙眼在盯著他。 - It is hard to be kept waiting, but it is an art to wait patiently.
被人等待固然是一種殘忍的行為學習等待卻也是一種至高的藝術。 - But even in the cruellest heart there are some fears too terrible to laugh at.
話雖這麼說，但即便是在最殘忍無情的人心裡，也埋藏著可怕得難以一笑置之的恐懼。
