Thank you for your help and I hope I can do something for you_____.

A. in return      B. in turn   C. in reply   D. by turns

Thank you for your help and I hope I can do something for you_____.

A. in return      B. in turn   C. in reply   D. by turns

Thank you for your help and I hope I can do something for you_____．

A．in return        B．in turn            C．in reply           D．by turns

Thank you for your timely instruction and encouragement. Without your valuable help, I ______in the examination.

A. will fail　 　　　　　B. have failed　　 　　　　C. would have failed　　 　　 D. must have failed