Focus on the pronunciation of hub
› the central or main part of something, where there is most activity: Property rentals in Mumbai, India's commercial hub, are the highest in the world. New Orleans has traditionally been the financial hub of southeast Louisiana.
› IT a machine that connects several computers together: an ethernet hub
at/in the hub of things › in the place where things happen and decisions are taken: It's that kind of attitude that will keep him in the hub of things for quite some time. → See also transportation hub, transport hub