A mentally ill man

The boy was killed by Yang Jiaqin, a mentally ill man who failed to receive adequate treatment.

这名男孩被没有得到充分治疗的精神病人杨家勤所杀。

According to neighbors and social workers, he is a gentle presence, possibly delusional and mentally ill, a quiet man who does not harass passers-by or panhandle aggressively.

据社区和社会工作者讲，他是一个温和的人，可能有妄想症及精神疾病，是一个安静的人，从不骚扰路人，也不是那种攻势乞讨者。

Emboldened, Denis plucked a mentally-ill man off the streets of Paris and performed a series of blood transfusions.

丹尼斯更大胆的将巴黎街头精神病人们进行了实验。