英语长难句子分析，急求！！！语法分析，句型分析，越详细越好。

Question

Only when a system possesses natural or artificial boundaries that associate the water within it with the hydrologic cycle may the entire system properly be termed hydrogeologic.
求求各位大神，救小女子一命！！！

Answer 1

associate the water within it with the hydrologic cycle是system的定语，形容是一个什么样的system, may是才能如何如何，这句话主语是system，谓语是may,
只有在天然与人工边缘并且能把水和水文分析模块连在一起的系统才能称为水文地质学。我翻译的不一定对啊，
http://baike.baidu.com/link?url=-eQ7Zmk-t8wcDiauwiZ6YYFBgJi41uFQra03CeSaQJSpwE2e5Jkv8JGsHWrDWCrCOAIaOT7cOG1wlVwp77UONK

Answer 2

Only when a system possesses natural or artificial boundaries that associate the water within it the hydrologic cycle may the entire system properly be termed hydrogeologic.

只有当一个系统拥有自然的或人工形成的边界来把系统中的水与水文循环联系起来的时候，才可以把整个系统恰当地称为水文地质学相关。

专业领域，翻译过来还是一头雾水。这个“边界”，应该指某种“定义”。典型的将简单事情复杂化的表达。

when....system be termed... 状语从句+主句；
that associate the water... with the hydrologic cycle 定语从句修饰boundaries. within it 修饰water.it指a system.
only放在句首，may倒装.