Why Manchester United and Liverpool are rivals?

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Tags

1. #construct
2. #became
3. #mancunian
4. #between
5. #cities
6. #consequently
7. #their
8. #decided
9. #liverpool
10. #manchester
11. #import
12. #english
13. #goods
14. #export
15. #exists
16. #level
17. #disenchanted
18. #rivalry
19. #merchants
20. #canal