题干

—We all had a lot of fun at the barbecue yesterday. Pity you weren’t there.
— I really should have gone with you, but I ________ on some remaining problems.
A.was workingB.would workC.workedD.had worked
上一题 下一题 0.64难度 单项选择 更新时间:2013-04-20 11:45:37

答案(点此获取答案解析)