penance
词根词缀：
impunity n. 不受惩罚
im 不 + pun 惩罚 + ity 具备某种性质，状况 → 不受惩罚
penal adj. 刑罚的
pen 惩罚 + al …的 → 刑罚的
penalize v. 处罚
penal〔= pen〕惩罚 + ize 使 → 处罚
penalty n. 惩罚
penal 刑罚的 + ty 表情况 → 惩罚
penance n. 赎罪
pen 惩罚 + ance 表状况 → 接受惩罚 → 赎罪
penitent adj. 后悔的
penit〔= pen〕惩罚 + ent 具有…性质的，关于…的 → 因受惩罚而后悔 → 后悔的
punish v. 惩罚
pun 惩罚 + ish 使… → 惩罚
punishment n. 惩罚
punish 惩罚 + ment 表结果 → 惩罚
repent v. 后悔
re 反 + pent〔= pen〕惩罚 → 反过来惩罚自己 → 后悔
数据来源：新东方英语词汇速记大全
相关例句：
He believed the death of his child was penance for his sins.
他认为孩子的死是对他罪过的惩罚。
Myrrh has been associated with bitter repentance, mortification of the flesh, and penance.
没药与痛苦的悔改，苦修，忏悔联合。
There is a period of penance, fasting, self-denial, and repentance.
有一个赎罪、斋戒、自制与忏悔的阶段。
If you really did penance you wouldn't have to.
如果你真的付钱赎罪可能就不用走了。
History slowly smothers its truth, but hastily struggles to revive it in the terrible penance of pain.
历史缓慢地将真理窒息，但又仓促地在忏悔巨大痛苦中竭力令其复活。
I mean, you've been banished to the tool shed to do your penance.
我是说，你都被放逐到工具储藏室来忏悔了。