Could you please revise these sentences.

I have two doubts concerning my previous post.
1) When I arrived at/on the farm (which preposition is best??)
2) A rabbit was thumping (its paw??) in the rabbit hutch
3) The theme of reversal of values is best embodied by the thee witches. Actually, they are not able to distinguish fair from foul, that is good from evil.
4) Macbeth starts as a brave hero and ends up as a murderous tyrant as a result of his thirst for power. He is remorseful but he refuses to aknowledge his guilt.He admits that if he had to aknowledge his crime, then it would be best for him not to know himself.
5) The second theme is that of regice, which, being an act against nature, brings about chaos and terrible weather conditions.

1) either = at might not necessarily mean "on"

5) What is "regice?" I do not know the word and only find it listed with Polémon, but no definition or synonyms.

Sra