stiffen
verb uk/ˈstɪf.ən/ us/ˈstɪf.ən/
(FIRM)
[ I ]变僵硬；变得不易弯曲
to become firm or more difficult to bend
Beat the cream until it begins to stiffen (= become firm). 将奶油搅至稠糊状。
His body stiffened in fear. 他吓得身体发僵。
(LESS RELAXED)
[ I ]变生硬，变得拘谨
to become less relaxed and more formal
She stiffened when her former husband walked into the room. 她的前夫走进房间时，她变得拘谨起来。
(MORE SEVERE)
[ I or T ]加强；（使）变得严厉；（使）变得艰难
to become or make something stronger or more difficult
These events have stiffened our resolve to succeed. 这些事件增强了我们争取成功的决心。
Penalties for selling illegal drugs have been stiffened. 对贩卖毒品的处罚加重了。
Stiffening competition in the market has led to a reduction in the company's profits this year. 市场日趋激烈的竞争导致了公司今年利润的下降。