求英语大神分析一下这个句子的成分!

问题描述:

求英语大神分析一下这个句子的成分!
There existed certain doubt among the students as to the necessity of the work.

倒装句式.
There existed 谓语
certain doubt 主语
mong the students 状语,修饰整句
as to the necessity of the work定语,修饰certain doubt