weaken
/ˈwi:kən; `wikən/ v
1 [I, Tn] (cause sb/sth to) become weak or weaker （使某人[某事物]）变弱
They watched her gradually weaken as the disease progressed. 他们观察到她随著病情变化身体也渐渐衰弱下去.
The dollar has weakened in international currency trading. 美元在国际货币交易中已趋疲软.
Hunger and disease had weakened his constitution. 他饥饿与疾病交加, 体质已削弱.
2 [I] become less determined or certain about sth; waver （对某事物的决心或肯定程度）减弱, 动摇, 犹豫
They have not yet agreed to our requests but they are clearly weakening. 他们还没有同意我们的要求, 但态度已明显软化.