战争中交战双方的残暴行为令人震惊。

The bestial acts committed by both sides during the war were shocking.

bestial 是由名词 beast（野兽）加上形容词后缀 -ial 构成的形容词。beast 指"野兽"，-ial 表示"具有...性质的"，所以 bestial 字面意思是"像野兽一样的"，引申为"残暴的、野蛮的"。