他残忍地对待小动物，这让人无法接受。

It's unacceptable that he is ___cruel to small animals.

嘲笑别人的缺点是一种残忍的行为。

Making fun of others' weaknesses is a ___cruel thing to do.

他残酷的批评让小女孩哭了起来。

His ___cruel criticism made the little girl cry.