SAT一道写作/语法/改错题

题目

SAT一道写作/语法/改错题
The bus would not have had to take the long detour instead of the main highway if the bridge did not become treacherous in the aftermath of an ice storm.
A.to take划线
B.instead of划线
C.did not become划线
D.in the aftermath of划线
E.no error
虚拟语气的情况下
主句为什么不是改成
if the bridge were not treacherous

答案

虚拟语气掌握主从句谓语动词的规范搭配：主句 从句　　与现在事实相反 would/情态动词过去式+do were (不分人称)/did　　与过去事实相反 would/情态动词过去式+have done had done　　与将来事实相反 would/情态动词...