问题
选择题
Without electronic computers，much of today’s__________advanced technology.
A．will not have been achieved
B．have not been achieved
C．would not have been achieved
D．had not been achieved
答案
C
这是一个含蓄虚拟条件句，通过介词短语without,表示潜在的一种假设，而主句中的情况也早已经发生，所以是对过去情况的一种假设，因此用would not have been achieved这一形式。