Question

英语题。求正确答案，及详细解析

Some people viewed the findings with caution ,nothing that a cause-and-effect relation-ship between passive smoking and cancer remains_.
A to have been shown B to have shown C to be shown D being shown

Answer 1

选C
some people viewed the findings with caution ,noting that a cause-and-effect relationship between passive smoking and cancer remained to be shown .
有些人对研究结果谨慎看待，注意到被动吸烟和癌症之间的因果联系还有待发现。

这里nothing that a cause-and-effect relationship between passive smoking and cancer remained 结合前面的意思就是说，之前得出的那些findings，谨慎地来说，就说明一点，被动吸烟和癌症之间的因果联系还有待发现（除了表明这点以外，这些findings意味着nothing）

Answer 2

应该选C吧

应该是“仍然有待证明”的意思

Answer 3

选C
remain的用法
1. 作系动词，意为"保持；仍然是"，相当于still be
2. 作不及物动词，意为"剩下"没有被动语态
3 it remains to be seen 留待。。。
后半句是定语从句，原型是 remains nothing to be shown
这个句子的意思是 一些人慎重地观察着条查结果，被动吸烟和癌症之间的因果关系已经没有再展示的必要了。
纯粹是我个人的理解 希望可以帮到你

Answer 4

选c
remain to do “有待于做”
此处为被动，“吸二手烟和患癌症间的因果关系还有待证明”