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

1. A.
   this
2. B.
   that
3. C.
   it
4. D.
   its

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

 A. this   B. that    C. its    D. it

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

   A. it　　 B. that　　　　　　 C. its　　　　　　 D. this

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

A. this　  B. that 　 C. its   D. it　　

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

A．this? B．that

C．its? D．it