This is 7th Grade Language arts and I had to do this last year.
Marley means that all he ever did was business. If there was something to do with business he accomplished it. He is also trying to teach Scrooge a lesson to not be stingy and be nice and not be greedy. Marley had to always to business and he was greedy and stingy just like scrooge and he doesn't want scrooge to be like that or he will end up being a ghost on chains.