大全-Ⅱ-16 以查 人傻智商低

fantasy06

For（原因表充分）
    only then（表必要） 是否意味着第一句话（黄色部分）一定要是第二句话（绿色部分）的充分必要条件？

大全-Ⅱ-16.  Instead of blaming an airline accident on pilot error, investigators should find out why the error was made by analyzing airplane design, airline management, and pilot-training programs.
     For only then can changes be made to ensure that the same type of error does not recur and cause another accident.

Which of the following is a presupposition of the argument above?

(A) Pilot error is not a contributing factor in most airline accidents.

(B) Airline companies themselves should be the agents who investigate airline accidents.

(C) Stricter government regulation of airline companies will make air travel significantly safer.

(D) Investigators of airline accidents should contribute to the prevention of future accidents.（D）

(E) Most pilots who make errors in flying will repeat their errors unless they are retrained.

erro does not recur and cause another accident 推出 investigators find out errors in design, management and training

investigators find out errors in design, management and training 也推出 erro does not recur and cause another accident

A和E 错是因为他们不充分吗？pilot training是事故不发生的必要条件，既然题目问假设，即结论成立的必要条件，何必要求假设要充分呢，即D，investigators should contribute to the prevention of future accidents--they are to find out erros in design, mana and training.

再次请教，多谢。

[此贴子已经被作者于2006-10-19 1:45:27编辑过]

fantasy06

up

pinkcutie

思考ing

xiangqinzh

应该是这样的

A=>B,但是NOT A不能=>B了

[此贴子已经被作者于2006-10-18 19:59:15编辑过]

rockmax

thanks xiangqinzh

smartsky11

才