请大家一定帮帮忙看看这题！GWD30-20

Researchers have announced that the magnetic fields emitted by one manufacturer’s security surveillance system, of which type there are 200,000 worldwide, can interfere with pacemakers and that this interaction can bring on missed or irregular heartbeats, nausea, breathlessness, dizziness, and even fainting.

1. of which type there are 200,000 worldwide, can interfere with pacemakers and that
2. of which, worldwide, there are 200,000 of that type, and which can interfere with pacemakers, and
3. of which type there are 200,000 worldwide, they can interfere with pacemakers and
4. 200,000 of which type exist worldwide, interfering with pacemakers, and
5. 200,000 of that type existing worldwide and can interfere with pacemakers, and

 想来想去不明白为何选D,这样一来不就是前一个分句没有谓语了吗？

谢谢！！

200,000 of which type exist worldwide, interfering with pacemakers, and

这题的答案我觉得是A。

D是没有谓语的，exist是作为分句的谓语，楼上的说法是不对的。只有A才有谓语动词，并且后面的and that和前面的that平行。其它选项and后面都没有that,破坏了和前面的announce that分句的平行，如果是做和主句并列也是不对的，因为and前面的宾语从句没有谓语，是sentence fragment.

yvonnege , r u sure D is the correct answer?

i agree with 香香茶,

 researchers announced two things..1, magnetic fields  ..can interfere with pacemakers ; 2, this interaction can bring on ...

"of which type there are 200,000 worldwide ' in A, modify "system"

i think A is best , even though it is perfect..

看到大家又在讨论这题很开心阿。

其实我考前作的新的几套GWD，发现很多答案都是错的，特别集中在阅读。因为语法争议比较少，而且因为是新题，论坛上几乎没有什么讨论。当时也很迷茫，像这道题，答案是D,我不服，论坛上也找不到，所以大家以后还是多讨论讨论吧。

我觉的如果选A，句子在意思上被两个独立的分句给割裂了

Researchers have announced that 。。。。。。。and that。。。。。

我觉得this interaction 这个主语时承接上一个分句 interfering with pacemakers的意思，在这点上看来，多加一个that显的很奇怪

我觉的是：

...

不对吧,这个exist只是which引导的句子中的动词,怎么能是that从句中的谓语呢,缺谓语~~

对于这道题,我有点看法:个人倾向A,但是觉得D也不一定有语法错误

个人觉得就前面部分来说D应该是由于A的,因为更简洁

不过D有个问题就似乎前面一个宾语从句有点fragment

有没有可能是这样

announced that the magnetic fields emitted by one manufacturer’s security surveillance system,200,000 of which type exist worldwide, interfering with pacemakers, and this interaction can bring ...

有色的字体部分是宾语从句的并列主语,中间都是修饰的成分

当然这样中间的修饰成分过长了似乎也比较awkward