Complex sentence: The X1 shares a similar platform with the BMW X3, based on the based on the same platform as the E91 BMW 3-Series Touring (wagon), and the EPA classifies the vehicle under the "Midsize Cars" category.
Split into simpler sentences: The X1 shares a similar platform with the BMW X3, based on the platform of the E91 BMW 3-Series Touring (wagon). The EPA classifies the vehicle under the "Midsize Cars" category.