他在报告中轻描淡写地提到了自己的贡献，尽管这些贡献对项目至关重要。

He understated his contributions in the report, though they were crucial to the project.

understated 是动词 understate 的过去式。understate 由前缀 under-（表示"不足、低于"）和动词 state（陈述）组成，字面意思是"陈述不足"，引申为"轻描淡写、低调处理"的意思。