demoralize
词根词缀：
demoralize v. 使士气消沉
de 非 + moral 道德 + ize 使… → 使没有士气 → 使士气消沉
moral adj. 道德的
mor 道德 + al …的 → 道德的
morale n. 士气
mor 道德 + ale →〔一群人〕有道德精神 → 士气
mores n. 道德观念；风俗
mor 道德 + es → 道德观念；风俗
数据来源：新东方英语词汇速记大全
相关例句：
I'd rather cut my throat than demoralize you on a day like this.
我情愿割断自己的脖子，也不想在这样的日子使你扫兴。
No matter in the earlier or later period, Lenin emphasized that international contradictions, especially those within imperialism should be made good use of to divide and demoralize their line of battle against socialist regime, and to strive line of lasting world peace.
不管是前期还是后期，列宁都强调在外交活动中应该充分利用国际上的矛盾尤其帝国主义营垒内部矛盾，去分化和瓦解敌人对付社会主义政权的联合阵线，争取持久的国际和平。
Demoralize the enemy from within by surprise, terror, sabotage, assassination. This is the war of the future.
用惊吓，恐怖，破坏，暗杀等手段削弱敌人，这才是未来的战争。
Rumors of impending sanctions can demoralize.
即将采取制裁的谣言能使士气低落。
Speculation in foreign exchange transactions will gravely corrupt and demoralize the party conduct and social values.
炒买炒卖外汇对党风和社会风气会起到严重的腐蚀败坏作用。
Clearly, one of the objectives is to demoralize the enemy troops in any way they can.
很明显，目标之一就是要用一切可能的手段打击敌军的士气。