hard as nails ------ 鐵石心腸(成語)
英文釋義
(IDIOM) Unyielding; lacking compassion; unsympathetic.
例句
The wealthy old woman was as hard as nails, and never gave help of any kind to her friends or family members if they were experiencing difficulties.
這位有錢的老婦人是鐵石心腸,在朋友或家人有困難時從不給他們任何形式的幫助。