Sentence:  Moreover , it allows the present management to reassign vehicles so that mileage will be more uniformly distributed throughout the fleet ; for example , if one driver <WSD>puts</WSD> on 22000 miles per year and another driver 8000 miles per year , their cars will be switched so that both cars will have 30000 miles after two years , rather than 44000 miles ( and related higher maintenance costs ) and 16000 miles respectively `` . 
Meaning of the word marked with <WSD> tags:  add to something existing