part可数吗?如果可数,Here is part of his talk.此句如何解释.

part是一个比较特殊的名词,即可数又不可数.只能特殊认识.常见重要用法如下：
part n.[c][u] a piece of sth.
* be part of=be a part of
e.g.Falling over is part of learning how to ski.=Falling over is a part of learning how to ski.
* part of = a part of (一小部分) / parts of （大部分）谢谢专家，那请问 be part of=be a part of 二者用法上有何差别没有任何差别，相等。特意查了英英字典，请您放，我不会胡乱做解释的。