humans=human beings?

humans=human beings? human beings humans区别? 请问human,humans,human being,human beings它们有什么区别以及他们可以通用吗? human beings are human beings look like human beings 中为什么不是humans,being为什么还要加s理由要充分 human ,human beings 区别 human being还是human beings? human beings是什么意思? human beings to program human humans的区别 Most cats remain suspicious of humans all their lives.改：Most cats are suspicious of human beings _______their lives.A.during B.throughout human beings与human being的区别 THE HUMAN USE OF HUMAN BEINGS怎么样 being VS human beings 区别! Care More for Human Beings? 英语高手帮忙翻译文章,急~The environment in which human beings exist is chemically complex.No part of that environment,however,is as chemically complex as the food and beverages humans routinely consume.The human diet includes substances th natural goodness of human beings什么意思 Water,Earth and Human Beings的意思