这个英语句子为什么是对的?

一般情况下help (to) do有助于help是使动词,后面接动词原形 ,heip doing 应该是不存在的.
另外,
1.help sb.to do sth.帮助某人做某事.
Can you help me to learn English 你能帮助我学英语吗?
I can't help you to lift this stone.我不能帮你搬这块石头.
2.be of some/ no/ much help to sb.对某人有些 / 没有 /
This book is of great help to me.这本书对我很有帮助.
Is this magazine of any help to you 这本杂志对你有些帮助吗?
3.help oneself （ to ）自用（食物等）.
Help yourself to the fish.请随便吃鱼.
Please help yourself to some pork.请随便吃点肉.
4.help sb.into/ out of 搀扶某人进入 / 走出.
He helped the patient out of the hospital.他搀扶病人走出了医院.
Can you help the patient into the hospital 你能搀扶病人进医院吗?
5.help sb.out 帮助某人克服困难,渡过难关、解决问题、完成工作.
When I'm in trouble,he always helps me out with money.每当我处境困难时,他总是用金钱帮助我渡过难关.
Please help me out with this problem.请帮我解这道试题.
6.with the help of 在……帮助下.
With the help of her,he found his lost child.在她的帮助下,他找到了失踪的小孩.
7.help sb.with sth.帮助某人做某事.
Please help me with my French.请帮我学法语.
Can you help him with this work 你能帮助他完成这项工作吗?
8.help to do sth.有助于做某事.
This program helps to improve our English.这个计划有助于我们提高英语成绩.
His speech helps to understand the policy.他的演讲有助于理解这个政策