trenchant
词根词缀：
entrench v. 用壕沟防护
en 使… + trench 切，割 → 在地上切割成〔壕沟〕→ 用壕沟防护
retrench v. 削减；节省
re 一再 + trench 切，割 → 一再削减〔开支〕→ 节省
trench n. 壕沟（像被切割出来的 → 壕沟）
trenchant adj. 一针见血的
trench 切，割 + ant …的，具有…性质的 → 像刀切进去一样 → 一针见血的
数据来源：新东方英语词汇速记大全
相关例句：
From the structure arrangement, the emphases of this paper is trenchant.
同时在结构安排上祥略有次，重点突出。
His comment was trenchant and perceptive.
他的评论既一针见血又鞭辟入里。
Geographic Environment is a huge and open system, which has quite trenchant arrangement and integration.
地理环境是一个开放的巨系统，系统本身又具有较为分明的层次性和综合性。
First, the lonely boar-spears and knives of the chase had been reddened as of old; then, had gleamed trenchant in the morning sunshine;
起先清冷的狩猎用的野猪矛和猎刀按往常一样先泛出红光，然后便在晨曦中清晰地闪亮；
Dorothy parker's writing is characterized by a trenchant wit and sophistication.
多罗茜帕克作品的特别是机智、老练。
Some of their comments were quite trenchant.
他们的有些批评十分尖锐。