human 就是单纯的指人类

humanity 书面用词，集合名词，多用于文学作品中，作人类解时，侧重有同情心、理解力和崇高品质。

humanity

n.(统称)人;人类;人性;人道;仁慈

复数： humanities

It helps engender a sense of common humanity

这有助于营造一种博爱的感觉。

It is for his humanity as much as his music that his numerous friends and pupils will remember him. He leaves a wife, son and daughter.

他的仁爱精神，以及他的音乐，都将长留在无数友人和学生的记忆里。他身后遗下妻子和一对儿女。

We want a peaceful environment for all humanity.

我们希望全人类拥有一个和平的生存环境。

We must never forget our humanity.

我们须永不忘记人性。

Humanity cannot tolerate such guilt.

人道主义不能容忍这种罪行。