问题补充:
As it turned out to be a small house party, we so formally.
A. needn’t dress up
B. shouldn’t dress up
C. were not necessary to dress up
D. needn’t have dressed up
答案:
A. needn’t dress up
B. shouldn’t dress up
C. were not necessary to dress up
(答案→)D. needn’t have dressed up
解析:考查虚拟语气。根据As it turned out to be中的过去时,说明这是与过去的事实相反的虚拟语气,故使用“情态动词+have done”的形式。Needn’t have done本不需要做某事实际上却做了。句意:正如结果所显示的那样,这是一个小型的家庭聚会,我们本不必要穿得如此的正式的。故D正确。