求教og中Neanderthals had a vocal tract that resembled those of the apes 一题

求教og中，

（Neanderthals had a vocal tract that resembled those of the apes）and so were probably without a language. 一题中答案是

(Neantherthals had a vocal tract resembling an ape's ),这里的用现在分词表示什么啊？Gmat的最常见考点不是伴随状态马？。。。

另外有个弱弱的问题，prenoun是什么东东啊。。。。^_^

分词单纯修饰名词vocal tract做定语呀...类似定语从句咯~这里不是伴随

谢谢ls^_^ 我的语法太差拉。。。。完全没有概念。。