【帮我看看这句英文对不对.定语从句There'safewpeopletowhomthedictionaryisuseful.二楼说的对，people虽是集合名词但表复数概念，谓语动词应该为复数。但我觉得to放在前面和后面都可以，比如MrJ】

　　帮我看看这句英文对不对.定语从句

　　There'safewpeopletowhomthedictionaryisuseful.

　　二楼说的对，people虽是集合名词但表复数概念，谓语动词应该为复数。

　　但我觉得to放在前面和后面都可以，比如

　　MrJones,forwhomIwasworking,wasverygenerousaboutovertimepayments.

　　MrJohnes,whomIwasworkingfor,wasverygenerousaboutovertimepayments.

　　另外towhom在定语从句中作什么成分？