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
OG 解释说had been 时态不对，应该用are allowed 表示过去持续到现在仍有效，那可不可以用havebeen 表示持续到现在仍有效呢？
Do not une the perfect tense when the simple tense will do. The GMAT prefer simplicy.
Wrong: Joe learned about an epoch in which dinosaurs had walked the earth. Right: Joe learned about an epoch in which dinosaurs walked the earth.
in the first example, the past perfect had walked is unecessary. Although the action had walked does take earlier than the action learned, th eariler action does not bearing on the context of the later action. The sequence of time does not need to be clarified or emphasized. Thus, the past perfect is considered wrong in this context.
You should use the pefect tense only when you can justify them with the rules described in these sections. if an action begin in the past and continue to the present (or its effect does), use the present perfect tense. If one action in the past precedes another, and you need to clarify or emphasize the time sequence, then use the past pefect. Otherwise, stick to the simple tenses.
The brand U2 was just one of many new groups on the rock music scene in the early 1980's, but less than then years later, U2 HAD fully ECLIPSED its early rivals in the pantheonof popular music.
The brand U2 was just one of many new groups on the rock music scene in the early 1980's, but less than then years later, U2 HAD fully ECLIPSED its early rivals in the pantheonof popular music.
京公网安备11010202008513号 京ICP证101109号 京ICP备12012021号
发表于 2012-4-15 23:37:20
收藏
收藏
