One Friday we were packing to leave for a weekend away my daughter heard cries for help.A

问题补充：

One Friday, we were packing to leave for a weekend away my daughter heard cries for help.

A. after

B. while

C. since

D. when

答案：

A. after

B. while

C. since

(答案→)D. when

解析：考察固定句型。Be doing sth when…正在做某事在这时…(意料之外的事情)；句意：在一个星期五，我们正在收拾书包准备去度周末在这时我的女儿听见了喊救命的声音。