就这一道题，帮帮忙，很简单，谢谢

Richardyu

In an attempt to produce premium oysters, a firm in Scotland has developed a prototype of a submersible oyster farm, sitting below the surface of the ocean, and it provides ideal conditions for the mollusks' growth.

A.farm, sitting below the surface of the ocean, and it provides

B.farm, sitting below the surface of the ocean for providing

C.farm that sits below the surface of the ocean and providing

D.farm that sits below the surface of the ocean and provides(D)

E.farm that is sitting below the surface of the ocean and it provides

问题，为什么D选项的and后面不加that？

zhangruizhi

因为这里的that从句是定语从句修饰farm，不是宾语从句，应该是在宾语从句中才必须要两个that不能省略。这里的provides和sits是平行结构

逆水潜龙

表示一系列动作，有顺承关系可以不加that。没人讲定从，宾从里并列必须加。加that是为了没歧义，以免and后与主句并列。因为动作不顺承可能是造成两个分句，若顺承就让其跟在that后。

我以前也喜欢研究这些规律，但发觉现在GMAT根本没有所谓的规律。一切以句意为主。别走弯路·