问题补充:
I supported him in time , otherwise heoff the bike .
A. might fall
B. would fall
C. should have fallen
D. would have fallen
答案:
A. might fall
B. would fall
C. should have fallen
(答案→)D. would have fallen
解析:otherwise 否则,相当于if not。本句可改为: if I hadn’t supported him in time, he off the bike。显然,这是与过去事实相反,主句应用would/could…+have done。故选D。