任性to act rashly out of a sense of injustice

生气to act in a fit of pique

• 他赌气没有来。

  He was angry and so didn't come.

• 小孩儿赌气不吃东西。

  The child stubbornly refused to eat anything.

• 他把书放在桌上，一赌气走了出去。

  He put the book on the table and left in a huff.