punishment
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：
Capital punishment is allowable only under exceptional circumstances.
只有特殊情况才允许执行死刑。
I have no doubt that the man is guilty and that he deserves punishment.
我毫不怀疑此人是罪有应得。
The punishment was out of all proportion to the crime.
罚不当罪。
He's caved in on capital punishment.
在是否应保留死刑的问题上，他已经让步了。
Punishment can never be an effective cure for acute social problems
惩罚绝不是解决严重社会问题的有效办法。
His punishment of death was commuted to life imprisonment.
他被从死刑减为无期徒刑。