ELI5: Exactly how do jet engines generate thrust?

So I've seen all the animations and read all the explanations of how they compress air, inject fuel, burn it, and run it through a turbine. For whatever reason, I can't get an intuitive grasp of how they actually generate thrust. With a rocket engine, it's obvious - expanding gas creates pressure in a chamber open on one side. However, jet engines are open on both ends, so why do the expanding gasses not just drive pressure out both ends?


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