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