Since the project has been on well you must it on until it is completed.A. carrying ca

问题补充：

Since the project has been on well, you must it on until it is completed.

A. carrying, carry

B. going, carry

C. going, go

D. carrying, go

答案：

A. carrying, carry

(答案→)B. going, carry

C. going, go

D. carrying, go

解析：原句意思是，这项工程进展顺利，你一定要坚持，直到它完工。表示动作从过去某一时间开始一直延续到现在，并且有可能持续下去，所以应该用现在完成进行时；carry on意思是继续，坚持下去，所以选B。