单项选择：—Howdidyoufinishtheworksoquickly?—Thecomputerhelpe...

问题详情：

单项选择：

— How did you finish the work so quickly?

—The computer helped me. It’s really _______ useful machine.

A. a                      B. an                     C. the                    D. one

【回答】

A

知识点：冠词

题型：选择题