关于prep-1-141和OG12-74的矛盾 请NN们看看

pennyrun

prep-1-141

The federal rules aimed at protecting human subjects of medical experiments were established to ensure that patients must be warned of potential risks and an independent panel would evaluate the experiment before it was conducted.  





 





(A) must be warned of potential risks and an independent panel would  





(B) must be warned of potential risks and that an independent panel  





(C) are warned about potential risks and that an independent panel  





(D) will be warned about potential risks and an independent panel would  





(E) would be warned of potential risks and that an independent panel would  

(C) are warned时态不正确，过去发生的事情应该用would(D) will be时态不正确，与后面的would也不平行；and后面缺少宾语从句引导词that。

OG12-74

In 1972 agreement between Canada and the United States reduced the amount of phosphates that municipalities had been allowed to dump into the Great Lakes.

(A) reduced the amount of phosphates that municipalities had been allowed to dump

(B) reduced the phosphate amount that municipalities had been dumping

(C) reduces the phosphate amount municipalities have been allowed to dump

(D) reduced the amount of phosphates that municipalities are allowed to dump

(E) reduces the amount of phosphates allowed for dumping by municipalities

这两题同样都是过去的法律或规定，为什么一个就能规定现在的事（第二题）， 另一个就只能用过去时呢？

说明一下第一题的解释是PREP笔记上的 我做的时候选对了  但是我觉得C不是错在时态  当时只是觉得ensure后面加原型怪怪的。。。

恳请各位NN给解释一下吧~

pennyrun

没有人啊 我来顶顶

pennyrun

ddddddd

zzlw89

我的理解是：第一题的would be是表明在federal rules 被发布以前病人并不会被告知潜在的风险，因此这里的时态是相对于过去（established）而言的将来时；第二题中之所以用are allowed 是因为市政府始终都是allowed to dump phosphates，并不会因为这个协议而变更。不知道这么说行不行~

pennyrun

谢谢~ 呵呵

hughlv

这道题我还是很不明白。为什么ensure后面的从句不应该用一般现在时态的。哪位nn来帮帮忙解释一下啊。。。

Jasonhere

an independent panel，evaluate(s)

红尘道士

第二题用were和are都是可以的
were暗示这个允许的排放量已经改变
are暗示，到现在还是这个排放量