Can someone explain the use of こと in these types of sentences?


Ok, still a newbie to Japanese. I've run across the word こと more and more
recently. I'm having a hard time understanding what effect it's having on the
sentence. For example, although I know the meaning of all the sentences below,
I can't tell you what こと means or what it's doing to the sentence. Can someone
give me some insight into its meaning? Thanks. See examples below

最初は国道を走りましたが、混んでいましたので、高速道路で行く **こと** にしました。 First I took the National Road,
but traffic was heavy, so we decided to take the subway.

トラックを追い越す **こと** は難しいです It’s hard to pass trucks.

静岡辺りでスピード違反でパトカーに捉まってしまいました。すごい罰金を払う **こと** になりました Around Shizuoka, we were
stopped by a police car for speeding. I had to pay a huge fine.

雨が降っていましたから、地下鉄で行く **こと** にしました Because it was raining, I decided to go by
subway




Syntactically こと is a
[nominalizer](http://en.wikipedia.org/wiki/Nominalization) in all these
sentences, i.e. it turns a verb into a noun by simple concatenation (e.g.
行くこと, 行く modifies こと).

Semantically,

  * [verb]+ことにする is a set phrase and means "to decide to [verb]"
  * [verb]+ことになる is also a set phrase and means "to turn out that [verb]".

[verb]ことは難しいです just means "[verb]ing is difficult" or "it is difficult to
[verb]".

* * *

Another nominalizer in Japanese is の. For a difference in usage see [this
question](https://japanese.stackexchange.com/questions/1395/what-is-the-
difference-between-the-nominalizers-%E3%81%93%E3%81%A8-and-%E3%81%AE).




Syntactically こと is a
[nominalizer](http://en.wikipedia.org/wiki/Nominalization) in all these
sentences, i.e. it turns a verb into a noun by simple concatenation (e.g.
行くこと, 行く modifies こと).

Semantically,

  * [verb]+ことにする is a set phrase and means "to decide to [verb]"
  * [verb]+ことになる is also a set phrase and means "to turn out that [verb]".

[verb]ことは難しいです just means "[verb]ing is difficult" or "it is difficult to
[verb]".

* * *

Another nominalizer in Japanese is の. For a difference in usage see [this
question](https://japanese.stackexchange.com/questions/1395/what-is-the-
difference-between-the-nominalizers-%E3%81%93%E3%81%A8-and-%E3%81%AE).

