Question

Freeze, freeze, thou bitter sky,

Answer 1

Answer:

Isn't it personification? Because the personification here is "That does not bite so nigh". By saying it bites, you are personificating it. ( If that makes sense

Answer 2

Answer:

The comparison in the passage above can best be rewritten as "The cold of the air is not as harsh as forgotten favors"

Explanation:

These lines make the comparison of the lack of gratitude of people and how does this reacting make other who are affected suffer, it is not talking about actual freezing or cold, it is about the insensibility of some and even more the coldness of humanity towards the ones that were of help for them in the past and from whom they got some benefit.