in the hope that 这里that是引导同位语从句吗

在Teenagers magazine - 青少年杂志上看到一句话：

Peopledressed baby boys in blue in the hope that boys would be protected.

请问专家：inthe hope that 这里that是引导同位语从句吗？整个in thehope that + 同位语从句是表目的吗？

另外，一般名词修饰名词，第一个名词要用单数，比如story book，但为何青少年杂志要用复数呢？

是的，that从句是hope的同位语从句。但一般不这么剖析，而是把in the hope that合起来剖析为复合连词，引导目的状语从句。

Teenagers Magazine = Teenagers' Magazine. 在非正式语体中，复数名词的属格的撇号常被省略。teenagers' magazine = magazine for teenagers. 比较：women's hospital = hospital for women.