Question

【题目】—_______ to keep our classroom clean and tidy.

—You are right.

A. That’s our duty B. This is our duty

C. It’s our duty D. The duty is

Answer 1

【答案】C

【解析】

试题分析：句意：保持我们的教室干净整洁是我们的职责。——你说的对。此句的动词不定式是真正的主语，用it放在句首作形式主语。故答案为C。