I don’t think possible to master a foreign language without much memory work.A. thisB. th

问题补充：

I don’t think possible to master a foreign language without much memory work.

A. this

B. that

C. its

D. it

答案：

A. this

B. that

C. its

D. it

解析：D

解析此处it用作形式宾语，真正的宾语是后面的动词不定式“to master a foreign language without much memory work”。