老师，我是您高中网络课堂的学生，听完了非谓语动词的三节后，有一种豁然开朗的感觉，今天在做五三这本书上的练习时，有这样一道题，我对答案非常有疑问，请您帮我解释一下！ Walter offered us a lift when he was leaving the office,but our work_______,we refused the offer. A.not finishing B.had not been finished C.not having f

D.not being finished. 这里是强调---当时---工作还末完，正确。你的答案也是正确的。I saw him coming现在分词做宾补