—We held a party for my grandpa’s birthday last night.—You must have had good time.A. ei

问题补充：

—We held a party for my grandpa’s birthday last night.

—You must have had good time.

A. eightieth; /

B. eightieth; a

C. eighty; a

D. eighty; /

答案：

A. eightieth; /

(答案→)B. eightieth; a

C. eighty; a

D. eighty; /

解析：句意： ---昨天晚上我们为我的爷爷举行了八十岁生日晚会。---你一定过的很愉快。当表达多少岁生日时，应该用相应的序数词，表达第……个生日。eighty 的序数词是eightieth。have a good time 是固定短语，过得高兴玩的愉快。