目睹了不公正，他觉得必须说出他的担忧。

Witnessing the injustice, he ___felt ___compelled ___to voice his concerns.

读完那份误导性的报告后，我觉得有必要写一份回应。

After reading the misleading report, I ___felt ___compelled ___to write a response.

她觉得必须说出真相，尽管这很困难。

She ___felt ___compelled ___to tell the truth, even though it was difficult.