og12 语法74题 have been allowed 和are allowed的区别

jiaying52

A 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

如果are allowed to dump可以的话，为什么不能用完成时have been allowed to dump表示这个条例持续到现在呢？

jiaying52

up

bunengwangmima

(D)    reduced the amount of phosphates that
municipalities are allowed to dump   关于这个时态还不是懂得很透彻啊？
一是不懂Lz的问题，二是不懂为啥不能用had been allowed，表示在法令reduced之前发生？？
求解答啊~~~~~~~~

lnl555

因为是reduced the amount  ，是减少数量而不是完全禁止，说明在签订协议的时候 phosphates 还在排放  所以不能用had been  

  have been  表示持续到现在  allow好像不能说持续吧  个人观点。。

小伊YSY

对于时态的问题不是很确定，个人确定have  been allowed 和are allowed 在这里都可以。
倒是C选项，我觉得主要错在另外的问题上，就是the phosphate amount 。这里应该改成the amount of phosphate。要求减少的是数量才对。
这里多个介词的表达法，更加清晰，重心也很明确。

maggie0324

我也很困惑这个问题。帮忙顶帖。

avernus

个人见解：

amount of phosphates that ....这句中已知that从句修饰amount
这里的amount应该可以有2种理解：
1.如OG上解释的，是现在的amount，  that从句的内容只是表示amount的情况，而与前句的时态无关，用are allowed表示agreement仍然执行，或者用were allowed 表是agreement不再执行了
2.这个amount是与reduced发生同时的amount，即过去的amount，此时应用were allowed表示当时被agreement允许倾倒的量



2种理解应该都行，不过OG的解释看着别扭些



而had been allowed 不对是因为不能reduced 已经完成的事情（had been allowed）

mlvince

我觉得2个都可以吧。但是reduce应该一定要用reduced

onlysilence222

对的，只是减少数量，不是完全禁止~~~所以不能用had been allowed

marshallzhu

我觉得2个都可以吧。但是reduce应该一定要用reduced

-- by 会员 mlvince (2011/3/15 22:01:56)

reduce 为什么一定要用 过去式？has reduced 不行么？
既然选D用are allowed，表明至今仍可以dump,那agreement 就从颁布后一直在减少（reduce），所以我觉得用has reduced的表明过去发生的事情一直持续到现在很合理啊~~
大家怎么看？？