動詞 weaken:

1. lessen the strength of
2. become weaker
3. destroy property or hinder normal operations
   同義詞：sabotage, undermine, countermine, counteract, subvert
4. reduce the level or intensity or size or scope of
   同義詞：de-escalate, step down
5. lessen in force or effect
   同義詞：dampen, damp, soften, break

1. Hunger and disease had weakened his constitution.
   他饑餓與疾病交加，體質(zhì)已削弱。
2. She weakened as the illness grew worse.
   隨著病情加重，她的身體日漸衰弱。
3. These internal disputes have weakened the party's power.
   這些內(nèi)部糾紛削弱了這個政黨的力量。
4. Nothing can weaken his resolve to become a lawyer.
   什么也動搖不了他要當(dāng)律師的決心。

weak.en

v.tr.intr.（及物動詞和不及物動詞）
weak.ened,weak.en.ing,weak.ens
To make or become weak or weaker.
使虛弱：使或成為虛弱或更弱

【引伸】
weak.ener
n.（名詞）