Why is 「で」 in 「三人のうちで一番...」 omissible but 「で」 in 「ここで待つ」 not?


Why is 「で」 in 「三人のうちで一番...」 omissible but 「で」 in 「ここで待つ」 not?

Are there any rough guidelines regarding whether a particle can be omitted or
not?




It's not really that で is omitted, but うち is diverted to something like
"conjunction" or "preposition" in English. It can lead a full sentence ("
_sentence_ (終止形) + うち") or a noun phrase (" _NP_ + のうち") to make an
**adverbial clause** (sentence adverb) that means " _in the course of; within_
". Sometimes, you can reword them using plain noun うち.

> **" adverbial" うち vs. "ordinary" うち**
>
> 学校に通う **うち** 、嫌でなくなってきた。 = 学校に通う **うちに** 、嫌でなくなってきた。  
>  三人の **うち** 一番背が高い。 = 三人の **うちで** 一番背が高い。  
>  乗客の **うち** 3名死亡、5名負傷 = ( _no equivalent_ )  
>  ( _no equivalent_ ) = 城壁の **うちを** 歩いて点検する。

Many other "formal nouns" (形式名詞) that refer to place or time, provide similar
usage; なか "in/amidst ...", うえ "as well as ...", もと "under ...", とき "when ...",
ところ "despite ..." etc., which more or less sound more high-register-ish or
formal than the noun + postposition form equivalent (if any).

Some ordinary nouns (結果, あげく, 瞬間 ...) are gradually acquiring such usages,
according to [this recent
research](http://www.ninjal.ac.jp/event/specialists/project-
meeting/files/JCLWorkshop_no3_papers/JCLWorkshop_No3_12.pdf).

