We were to go out for a camp it began to rain.A. hardly; thanB. around; asC. about; when

问题补充：

We were to go out for a camp it began to rain.

A. hardly; than

B. around; as

C. about; when

D. nearly; while

答案：

A. hardly; than

B. around; as

(答案→)C. about; when

D. nearly; while

解析：句意，我们正要外出宿营时，突然开始下雨了。Be about to表示马上就要发生的事情，故选C。