It’s8 o’clock. My mother is reading a book. My sister and I .A. is doing my homeworkB. am

问题补充：

It’s8 o’clock. My mother is reading a book. My sister and I .

A. is doing my homework

B. am doing my homework

C. is doing our homework

D. are doing our homework

答案：

A. is doing my homework

B. am doing my homework

C. is doing our homework

(答案→)D. are doing our homework

解析：句意：八点了。我的母亲正在读书。我的姐姐和我正在做作业。下文my sister and I表示复数含义，故谓语动词用复数形式，选D。