Humans are highly complex social primates and, because of this, our responses to the world can be difficult to explain with simple biology or neurotransmitters.
人类是高度复杂的社会性灵长类动物，所以我们对外界的反应很难用单纯的生物学或神经传递素来解释。
2
It occupies a special place in social interaction and is a fascinating feature of our biology, with motor, emotional and cognitive components.
笑在社会交往中占据重要的位置，是人类生物学中一个迷人的特征，包含了运动、情绪和认知成分在内。
3
Digital media will be good for you, as will be the area of biology, science, the humanities and social work, charities, and the "green" movement.