口语在协调的具体过程中用得较多，协调结果一旦形成则无需要用书面语予以确定。
参考答案：错
—Tom is ill in hospital.
—Oh, I didn't know about that._________, I'll go and see him. [ ]
A. If so
B. If anything
C. If any
D. If ever
自动驾驶仪采用是（）控制.
A.开环自动
B.闭环自动
C.开环手动
D.闭环手动
