Finally save your document before you your computer.A. turn onB. turn upC. turn offD. tu

问题补充：

Finally, save your document before you your computer.

A. turn on

B. turn up

C. turn off

D. turn down

答案：

A. turn on

B. turn up

(答案→)C. turn off

D. turn down

解析：本题的含义是在你关闭电脑之前，把你的文档保存一下，turn off是关上的意思，故本题选C。