—Whyareyourhandsthatdirty?        —Oh,I

问题详情：

 — Why are your hands that dirty?

         — Oh, I______ in the garden since we finished breakfast.

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

【回答】

D

知识点：现在完成时及其被动式

题型：选择题