stiffen

动词 stiffen:

1. become stiff or stiffer
2. make stiff or stiffer
3. restrict
   同义词：tighten, tighten up, constrain

1. The promise of a reward might stiffen their resolve.
   答应给他们奖励可以坚定他们的决心。
2. He stiffened at the insult.
   他听到这些侮辱的话，态度强硬起来。