OG194:  强烈要求牛们来解释一个基础概念,

smartcoco,

1. presenter 是前一句的主语,在它的同位语中presenter 放在了介词of 之后, 形成一个"介宾"结构: one of presenters.

2. presenter 就可以以them 或whom 的形式出现

3. 但在这里用了只能用whom , 否则用them就是run-on 问题

谢谢weiwei2004，你这么解释我觉得很清楚。但还是很弱的问一下：什么样的问题是run-on的问题？在og里我看到很多这样的问题，而且我也看到了别人举的例子,在http://forum.chasedream.com/dispbbs.asp?BoardID=23&ID=32238&replyID=&skin=0这个帖子里面，guandream指出runon sentence:two or more sentences are connected using comma or not, but they are independent sentences. correction: using conjunction , conjunction adverb , semicom and comma or seperating two sentences using point.

在这个题目里面，我觉得即使是one of them也没有错呀。是不是可以改成

Presenters at the seminar will demostrate adaptive equipment that allows visually impaired people to use computers,and one of them is blind.这个句子是不是run-on呢

Presenters at the seminar will demostrate adaptive equipment that allows visually impaired people to use computers,and one of them is blind.这个句子是不是run-on呢

对于是不是run on，我不太清楚，但是这个句子是肯定不行的。

１、them指代不清

２、句子重心发生了改变。