在某人帮助下

with one's help或者under the help of sb
一般来说，可以把sb.和one'看成是同义词，sb.一般是人名等之类的名词，one'一般是名词所有格或名词性物主代词。

eg: (1) with Tom' help
(2) with his help
(3) under the help of Tom

with the help of sb

with one's help

一般以英语为口语的国家的人是讲 with one's help

with one's help
with the help of sb

with the help of sb