The young boy found hard to finish the work alone.A. thatB. thisC. itD. which

问题补充：

The young boy found hard to finish the work alone.

A. that

B. this

C. it

D. which

答案：

A. that

B. this

(答案→)C. it

D. which

解析：find后可加宾语从句，选A的话，宾语从句缺少主语谓语（it was）；find it +adj.作宾补，it是形式宾语，真正的宾语是动词不定式；故选C。