高等继续教育 / 大学英语II
正确率：100%
题型描述: 单选题
He didn’t show up at the party yesterday. He ＿＿＿＿ in the lab.
A.must be busy to work
B.must have been busy working
C.would have been busy working
D.must be busy wording
He didn’t show up at the party yesterday. He ＿＿＿＿ in the lab.
A.must be busy to work
B.must have been busy working
C.would have been busy working
D.must be busy wording
参考答案：
佳题速递：