语法与词汇 Perhaps even more important than the accuracy and realibility of a m...cal instrument ___.

A、 that positioning it is correct
B、 is positioned correctly
C、 that its correct position
D、 is that it be positioned correctly

【正确答案】 D

【答案解析】前半句是说或许比这个什么工具的精确度和可靠度更重要的，当然就缺be+宾语。排除A,C。注意很容易误选B.中文：是被放置地正确。想当然英文:is positioned correctly.须知这里要用两个be动词。“是被放置的正确”当中，“是”要be，“被”也要一个be。B项一个嘛，显然错。选D.