Simplify the following text for a Grade 9 native English-speaking person.
Original: Departing from Roman military traditions , Fabius adopted the strategy named after him : avoiding open battle , while placing several Roman armies in Hannibalâ s vicinity in order to watch and limit his movement .
Simplified: Fabius adopted the Fabian strategy . He refused open battle with his enemy while placing several Roman armies in Hannibalâ s vicinity to limit his movement .