–Haveyouworkedoutthescheduleforourgraduationtrip? –Yes....

问题详情：

– Have you worked out the schedule for our graduation trip?

  – Yes. I ________ on it for almost 4 hours. 

  A. was working      B. had worked                     C. worked             D. have been working

【回答】

C

知识点：一般过去时及其被动式

题型：选择题