og148

148. Under the Safe Drinking Water Act, the Environ­mental Protection Agency is required either to approve individual state plans for controlling the discharge of wastes into underground water or that they enforce their own plan for states without adequate regulations.

(A)  that they enforce their

(B)  for enforcing their

(C)  they should enforce their

(D)  it should enforce its

(E)   to enforce its

E, the best choice, is the only one that maintains grammatical parallelism by using an infinitive--to enforce--to complete the construction either to approve ... or.... All of the other choices offer syntactic structures that are not parallel to the infinitive phrase to approve. In addition, choices A, B, and C use plural pronouns (they and their) that have no grammatical referents.

My Question is: why use "controlling", not "to control"? Because the sentence has a previous “to do” or other reason? Usually we use “do sth to do” to express the purpose of verb.

EPA is required either to approve individual state plans for controlling the discharge of waste into underground water.

plan for 是固定用法:  为....作计划,打算

何况,你细读几遍,..is required..to approve individual state plans for controlling the discharge ...

感觉远好于...is required..to approve individual state plans to control  the discharge ...

i think the plan is a noun in this sentence .

plan在这里是名词

longman上面有plan for sth.和plan to do sth.

这里为什么要用for controlling?

有沒有MM知道

我不是MM，我的想法是动名词doing和不定式to do 表达的意思有区别。doing有重复、持续、正在做的含义，to do有将要做但未做的含义。不知这样的说法行不？

另外也要跟下文的for states...对应吧。

Plans for controlling...这里的for后面的词组是修饰计划。

如果用to，就产生了歧义，说明agency要去control，例如， I am required to find a method to resolve this problem.  或者更简单明显一些， I want to find a glass to drink water.

总结一下，以便参阅：

Plan

1、名词.

（1）plan of sth

a plan of attack.进攻的计划

（2）plan for （doing） sth

had no plans for the evening.没有今晚的安排

plan for controlling the discharge of wastes into underground water

动名词作介词for的宾语表示长期的、重复的、持续的动作

（3）plan to do something

plans to turn the site of the factory into a park

不定式做名词plan的定语，表示将要做但未做的动作。

2、动词

(1)plan to do sth.

They plan to buy a house.他们打算买一房子

(2)plan sth.

plan a campaign.拟订竞选计划