—Mum,Tomisalwaysworkinglateintonight.Idon'tknowwhatheis...

问题详情：

—Mum, Tom is always working late into night. I don't know what he is busy doing.:状_元_源Z_—Oh ,he _____for his new project.

A. has prepared   B. had prepared   C. has been preparing   D. was preparing

【回答】

C

知识点：现在完成进行时及其被动式

题型：选择题