题干
______ for two days, Steve managed to finish his report on schedule.
A：To work
B：Worked
C：To be working
D：Having worked
答案(点此获取答案解析）
D
______ for two days, Steve managed to finish his report on schedule.
A：To work
B：Worked
C：To be working
D：Having worked
此认识正确的是（ ）
