He often writes to us expressing his hope ________ he'll come to see us when he finishes his training course.

1. A.
   which
2. B.
   that
3. C.
   what
4. D.
   whether

He often writes to us expressing his hope ______ he’ll come to see us when he returns to China.

   A. which            B. that              C. what               D. whether

 He often writes to us expressing his hope ________ he'll come to see us when Macao returns to China.

A. which B. that C. what D. whether

He often writes to us expressing his hope ________ he'll come to see us when he finishes his training course.

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