We don’t know it next. Let’s go and ask Mr. Li.A. what to doB. to do whatC. whether to do

问题补充：

We don’t know it next. Let’s go and ask Mr. Li.

A. what to do

B. to do what

C. whether to do

D. to do whether

答案：

A. what to do

B. to do what

(答案→)C. whether to do

D. to do whether

解析：考查宾语从句.句意:我们不知道接下来是否做这件事.从句中不缺少宾语,故选C.