help to do为什么to可以省略

当动词help后接不定式用作宾语或宾语补足语时，该不定式可以不带to，用于help(to) do sth或help sb(to)do sth。例句：I helped(to)wash the car.我帮忙洗车。

例句

He helped (to) do the work.

他帮助做这工作。

We helped her (to) find her things.

我们帮她找东西。

I helped him (to) repair his bike.

我帮他修自行车。