- In Sugarcandy Mountain it was Sunday seven days a week, clover was in season all the year round, and lump sugar and linseed cake grew on the hedges.
- Even the ducks and hens toiled to and fro all day in the sun, carrying tiny wisps of hay in their beaks.
These was quoted from Animal Farm. I googled the difference between all + day/month/year and all + the + day/month/year, and found that the expression with the is quite old-fashioned expression. That makes sense because Orwell lived in the old time. However in the #2 sentence, the expression without the is used.
What's the difference in nuance between these two sentences? (all the year round / all day)
Are they exchangeable? (e.g. all year round / all the day)
What's the point in keeping this inconsistency in the same book?