1.Before long you will see a paper, a quite important paper for which several men and women have risked their lives...

【参考译文】不久你就可以看到一份文件，一份非常重要的文件、几名男女为之冒生命危险的文件...
【结构解析】before long 意思是“不久以后”，“for which several men...”做定语修饰“paper”，其中的"for"承“risk”，即risk for sth.为某事冒险。

2.you gave me quite a start...

【参考译文】你真的让我吃了一惊...
【结构解析】start此处做名词，意思是“惊动、吃惊”。

3.This is the second time in a month that somebody has gotten into my room off that confounded balcony!

【参考译文】这是本月第二次有人从那个讨厌的阳台进入我的房间！
【结构解析】这里用的固定结构是"This/it is the +序数词+that sb. had done sth",句中sb.后一定要用完成时。