to which在这里怎么解释?

to which在这里怎么解释?A draft of a U.N. Security Council resolution being circulated Tuesday called for "full and immediate compliance with the cease-fire agreement to which the parties have subscribed" and the immediate withdrawal of Russian forces.感觉to是多余的,如果不多余,在这里充当什么成分?the parties have subscribed就是agreement,在还后当定语感觉比较正确,但多了to,to是和compliance连接吗?那中间的with the cease-fire agreement就很怪异.介词to也值得商榷.根据我找到的资料，这里可以改用that，但改了that，to就不能提前了。下面都是正确的：agreement which the parties have subscribed toagreement that the parties have subscribed toagreement the parties have subscribed to很感谢几位回答，是否有异议？呵呵，Arabella1120 如果有兴趣，我还有一个疑问，希望找到答案。就是固定动词短语介词不能提前，比如look for，This is the book you are looking for不能说成This is the book for which you are looking，但是据说以前按古老的非常严谨的语法规范，介词是不能放在句尾的，那个时候如果想表达这样的意思该怎么办？还是说“固定动词短语介词不能提前”这条语法是在语法规范放松以后才有的？