The expert offered us another piece of a
题型:选择题
问题:
The expert offered us another piece of advice , ___ of great help to our program.
A.I think it is
B.I think which is
C.which I think it is
D.which I think is
The expert offered us another piece of advice , ___ of great help to our program.
A.I think it is
B.I think which is
C.which I think it is
D.which I think is