The 2007 Jeep Liberty's drivetrain needs to be disconnected to prevent damage to the transmission. This is typically achieved through a device called a "tow dolly" (which lifts the front two wheels) or a "drive shaft disconnect". Flat towing (all four wheels on the ground) requires specific modifications or an appropriate tow package, which is *not* standard.
Before towing, consult your Jeep Liberty's owner's manual and a reputable towing specialist to determine the correct towing method and any necessary modifications. Incorrect towing can severely damage the vehicle's transmission and drivetrain.