---you having supper at this time yesterday?---No I was.A. Are; having a restB. Were; rea

问题补充：

---you having supper at this time yesterday?

---No, I was.

A. Are; having a rest

B. Were; read a book

C. Are; watching TV

D. Were; singing

答案：

A. Are; having a rest

B. Were; read a book

C. Are; watching TV

(答案→)D. Were; singing

解析：have a rest休息；read a book读书；watch TV看电视；sing唱歌。句意：昨晚这个时候你正在吃晚饭吗？结合语境可知下文描述的是过去正在进行的动作，故选D。