【俚语】

Pigheaded 顽固的，固执的

【例句】

Never have I met a woman so pigheaded!
我从来没见到过这样固执的女人。

Stubborn /ˈstʌbɚn/ 顽固的，固执的

【例句】

He's very stubborn and it drives me mad sometimes.
他很固执，有时候会把我逼疯。

Be as stubborn as a mule
倔得和驴一样

【例句】

I tried to convince Jake to go to the doctor, but he's as stubborn as a mule.
我试着让Jake去看医生，但他倔得和驴一样。

Set in one's ways 不愿改变

【例句】

As he gets older he's becoming more set in his ways.
年级慢慢大了，他越发不愿意改变自己。

inflexible 不愿改变的

【例句】

My boss is kind of inflexible and he does everything by the book.
我的老板有点死板，什么事都照本宣科。