－Is that a ruler?－No .A. it isB. it isn’tC. that isD. that isn ’t

问题补充：

－Is that a ruler?

－No, .

A. it is

B. it isn’t

C. that is

D. that isn ’t

答案：

A. it is

(答案→)B. it isn’t

C. that is

D. that isn ’t

解析：对于be动词帮助句子构成一般疑问句，其肯定回答用Yes，it is。或No,it

Isn’t.故选答案为B