Are these sentences grammatical? And if not, could you rewrite for me or explain what’s wrong inside? Please
After the inauguration, I saw the new elected mayor lying inside his new office in proneness with a dagger pierced through his throat, many people guess that it might be done by his new hired porter.
On my way home I saw 4 porters moved the coronation coach, showing sharp malice from their eyes.
I got into the habit of treating racist with tremendous malice when I once saw a racist stepped over a prone black infant.

Hey,

I think it could possibly be:
After the inauguration, I saw the newly elected mayor lying in a prone position inside his new office with a dagger pierced through his throat. Many people guessed that it might have been done by his newly hired porter.
On my way home, I saw four porters moving the coronation coach, showing sharp malice in their eyes.
I got into the habit of treating racists with tremendous malice after I once saw a racist step over a prone black infant.

I changed "proneness" because it means tendency or inclination. I don't think I'm good enough at explanations to explain the rest. Hope I helped a bit.

Daisy