it rain tomorrow we would have to cancel the football match.A. WereB. WouldC. Should D.

问题补充：

it rain tomorrow, we would have to cancel the football match.

A. Were

B. Would

C. Should

D. Will

答案：

A. Were

B. Would

(答案→)C. Should

D. Will

解析：句意：如果明天下雨，我们就不得不取消足球比赛。根据主句的would have to…，可知这是和将来相反的虚拟条件句，条件句的谓语可以用should do/did/Were to do，也可以省略if，提前should，were，但是如果是were的话，it后面要有to，所以选C。