What is this 行ってまいります


資料が届いたようですので、事務室に取りに行ってまいります。 "Because it looks like the documents have
arrived, I go to the office to fetch them."

This sentence is an example from the grammar section of my textbook. I've
encountered this 行ってまいります only once before (at least as far as I can
remember), and I couldn't beat much sense into it. When I search for まいります/まいる
on jisho, I find nothing. I can search for 行ってまいります and find this
<http://jisho.org/search/ittemairimasu> . But since the result is a set phrase
which has a meaning which doesn't even apply in this case here, it doesn't
help much.




参る【まいる】 is a **humble** equivalent of 来る and 行く. If you don't know about
humble expressions (or _keigo_ in general), refer to your textbook about
honorific/humble expressions. 参る is one of the most basic humble verbs. You
can find an online article, for example
[this](https://en.wikipedia.org/wiki/Honorific_speech_in_Japanese#Humble_language).

So 行ってまいります is 行ってきます said in a humble manner.

If 行ってきます still makes little sense to you, this きます is a subsidiary verb, a
verb that can follow the te-form of another verb for special purposes. See:
[What is a subsidiary verb?](https://japanese.stackexchange.com/q/18952/5010)
and [Meaning of くる in
鼻の奥まで染みこんでくる](https://japanese.stackexchange.com/q/33624/5010)

So 行ってきます/行ってまいります implies you will go to somewhere, do something there, and
_return here_.

> ロンドンに行ってきました。  
>  ロンドンに行ってまいりました。(humble)  
>  I went to London (and already returned from London).




参る【まいる】 is a **humble** equivalent of 来る and 行く. If you don't know about
humble expressions (or _keigo_ in general), refer to your textbook about
honorific/humble expressions. 参る is one of the most basic humble verbs. You
can find an online article, for example
[this](https://en.wikipedia.org/wiki/Honorific_speech_in_Japanese#Humble_language).

So 行ってまいります is 行ってきます said in a humble manner.

If 行ってきます still makes little sense to you, this きます is a subsidiary verb, a
verb that can follow the te-form of another verb for special purposes. See:
[What is a subsidiary verb?](https://japanese.stackexchange.com/q/18952/5010)
and [Meaning of くる in
鼻の奥まで染みこんでくる](https://japanese.stackexchange.com/q/33624/5010)

So 行ってきます/行ってまいります implies you will go to somewhere, do something there, and
_return here_.

> ロンドンに行ってきました。  
>  ロンドンに行ってまいりました。(humble)  
>  I went to London (and already returned from London).

