他坚决抗议对他的指控。

He firmly ___protested the accusations against him.

学生们举着标语牌在校长办公室前抗议不公平的评分制度。

The students ___protested in front of the principal's office, holding signs against the unfair grading system.

他坚决抗议对他的指控，声称自己是无辜的。

He ___protested his innocence when accused of the crime.