在线等！OG13-81关于时态的问题

credo1992

求教！OG13——81
Fossils of the arm of a sloth found in Puerto Rico in 1991, and dated at 34 million years old, made it the earliest known mammal of the Greater Antilles Islands.

• A  sloth found in Puerto Rico in 1991, and dated at 34 million years old, made it the earliest known mammal of
• B  sloth, that they found in Puerto Rico in 1991, has been dated at 34 million years old, thus making it the earliest mammal known on
• C  sloth that was found in Puerto Rico in 1991, was dated at 34 million years old, making this the earliest known mammal of
• D  sloth, found in Puerto Rico in 1991, have been dated at 34 million years old, making the sloth the earliest known mammal on
• E  sloth which, found in Puerto Rico in 1991, was dated at 34 million years old, made the sloth the earliest known mammal of
  

答案是D，我做对了，凭借几个point。但看了论坛上的几篇讨论我仍有问题

主干：Fossils ...  have been dated at 34 million years old,....
为什么主谓语动词dated要用have been dated？后面是 at 34 million years，并不表示过去的一段时间啊！这里我预想的应该是用were dated表示过去的某个时间比较切当！

Amber.C

参考 OG13 page669
Present perfect: Used with has or have, the present perfect tense describes an action that occurred at an indefinite time in the past or that began in the past and continues into the present.
如果用 were，表示过去date，而非至今为止的date。用were dated，需要明确的时间点，或者上下文有提示。

另外可以用排除法做，选出D。

credo1992

Amber.C 发表于 2014-8-4 15:52
参考 OG13 page669
Present perfect: Used with has or have, the present perfect tense describes an act ...

谢谢你的帮助。这题我也是用排除法做对的，但就是感觉have been dated让我看着很不习惯。 根据quote的内容，是否就是说句子中对于一个过去但不确定的时间点，时态要用present perfect?  如果说动作的延长性，date作为一个即时动词，表示一段时间的动作恐怕不合适吧？

Amber.C

时态的选择表明的是一个tense的问题，这样想就理解了。tense和action的区别。

credo1992

Amber.C 发表于 2014-8-4 16:31
时态的选择表明的是一个tense的问题，这样想就理解了。tense和action的区别。

其实这么一说我更晕了-。-什么是tense和action的区别

旺财财

credo1992 发表于 2014-8-4 21:36
其实这么一说我更晕了-。-什么是tense和action的区别

抱歉来晚了。我贴个外国论坛大N的解释给亲吧，~~~
"1) 代词不能指代介词短语中的的宾语（不绝对）
2) 这里have been比were好么？
Present perfect probably makes a little bit more sense, since the findings clearly have direct relevance to the situation being discussed at present. However, it would certainly not be incorrect to use the simple past (although that usage would suggest that the findings no longer have relevance, possibly because they have been superseded by some more recent findings).
3) D选项中found不会歧义指代sloth？
Like many other modifiers, this one requires you to use common sense to identify its referent. Grammatically, it could technically stand for either of these; however, since only one of them makes any sense, it is not ambiguous.

"
欢迎亲去戳我的帖
http://forum.chasedream.com/thread-917023-1-1.html~~也是这道题我也有个小问问~~~
谢过

credo1992

旺财财 发表于 2014-9-4 09:27
抱歉来晚了。我贴个外国论坛大N的解释给亲吧，~~~
"1) 代词不能指代介词短语中的的宾语（不绝对）
2) 这 ...

感谢帮助！原来是可用可不用的问题...话说兄台帖子我看过了。不过关于of 和 on在那里的用法，我一新人倒真说不出来太多想法，只是觉得也是 “可用可不用” 的问题。就不在兄台帖子下献丑啦~

旺财财

credo1992 发表于 2014-9-4 14:30
感谢帮助！原来是可用可不用的问题...话说兄台帖子我看过了。不过关于of 和 on在那里的用法，我一新人倒 ...

客气了。都是互相学习得别见外。