You can’t imagine this lake used to be a beautiful place in our province.A. at any timeB.

问题补充：

You can’t imagine this lake used to be a beautiful place in our province.

A. at any time

B. at one time

C. in no time

D. at times

答案：

A. at any time

(答案→)B. at one time

C. in no time

D. at times

解析：考察介词短语辨析。A无论如何；B以前曾经；C离开，马上；D时而不时；句意：你无法想象这个湖曾经是我们省里一个非常美丽的地方。根据句意说明B正确。