菜鸟再问一个逻辑

  often patients with ankle fractures that are stable, and thus do not require surgery, are given follow-up X-rays because their orthopedists are concerned about possibly having misjudged the stablilty of the fracture. When a number of follow-up X-rays were reviewed, however, all the fractures that had initially been judged stable were found to have healed correctly. Therefore, it is a waste of money to order follow-up x-rays of ankle fracture initially judged stable

  support

   A:  doctors who are general practitioners rather than orthpedists are less likely than orthpedists to judge the stability of an ankle fracture correctly

   B:  many ankle injuries for which an initial x-rays is ordered are revealed by the x-ray not to invlove any fracture of the ankle.

   C:  X-rays of patients of many different orthopedists working in several hospitals are reviewed

    D:  the healing of ankle fractures that have been surgically reqired is always checked by means of a follow-up x-ray

    E:  orthopedists routinely order follow-up x-rays for fractures of bone other than ankle bones

    这个题目其实很简单，但我水平太菜，看到答案了，只是模糊的觉得其对，但是似乎还是没理清其中逻辑关系，请NN确认一下答案，并指点一下理由，谢谢谢谢！！！！

I choose E.

看看睡熊GG的这个总结对你会不会有帮助?

"可以加强的形式有：

（1）A有效并保持；（2）B可能；（3）~A -> ~B (否命题型加强)；（4）A -> B （原文改写型加强）"

此题的加强方式正是(1)

判断的原则是：对于A -> B,

可以加强的形式有：

（1）A有效并保持；（2）B可能；（3）~A -> ~B (否命题型加强)；（4）A -> B （原文改写型加强）

可以削弱的形式有：

（1）A无效或已不保持；（2）B不可能；（3）B -> A (因果关系颠倒型削弱)；（4）A -> ~B (否定结论型削弱)

其它形式都不构成加强或削弱。对照你找到的所有例子，看看是不是已经非常清楚了

觉得很简明而且有启发性.至于睡熊有没有进行其它系统的总结,我就不知道了.

   恩，好总结 ！！