Question

【题目】It is our duty _________our classroom clean and tidy.

A. to keepB. keepsC. keepingD. kept

Answer 1

【答案】A

【解析】

保持我们的教室整洁干净是我们的职责。本题考查动词不定式作表语。our duty 是真正的主语 ,前面那个it 是逻辑主语 ，to keep是表语 动词不定时作表语，还原后是：our duty is to keep our classroom and tidy。故选A。