She wrote a letter of apology but only under protest.

她无奈之下写了一封致歉信。

《牛津词典》

They agreed to the proposal under protest.

他们不情愿地答应了这个提议。

youdao

I'm only here under protest, ' Jenna said shortly.

“我是被迫来的，”詹纳不耐烦地说。

youdao

Mister Chavez often went for long periods without food to protest the conditions under which the farm workers were forced to do their jobs.

VOA: special.2009.09.06

All 12 have agreed to fulfil their existing obligations in good faith, but under protest.

BBC: Saracens players shocked at exits

As part of the Merkel cabinet, he supported the Magna deal under protest, arguing that insolvency arrangements might best determine the value of Opel.

FORBES: Opel's Bumpy Ride

Girardi wanted the game played under protest.

WSJ: Girardi Outburst Spurs Yankees to Victory