The best way to learn proper English is to read news report, and watch news on TV. Watching TV shows is a great way to learn casual English, slang words, understand culture reference and humor. If you have already watched these shows then you may recall the words used in the following dialogs.

are one heart, one flesh, one SOUL.
Game of Thrones Season 4, Episode 2

Now his SOUL is so light,
Game of Thrones Season 5, Episode 7

May God rest your SOUL,
Brother Cenwulf.
Vikings Season 1, Episode 3

at least let my SOUL escape."
Money Heist Season 1, Episode 1

But you have to swear
you'll never tell another SOUL.
Game of Thrones Season 8, Episode 4