【题目】________ for two days, Jessica managed to finish her project ahead of time.
A. To work B. Worked
C. To be working D. Having worked
在线课程【答案】D
【解析】
试题分析：考查非谓语动词 句意：Jessica已经工作两天，他提前完成任务。两个句子共用一个主语Jessica，Jessica与work之间是主谓关系，且发生在主句之前，故选D项。
考点 : 考查非谓语动词