(=> (and (instance ?SKI SnowSki) (material ?MAT ?SKI)) (or (subclass ?MAT Metal) (subclass ?MAT Wood) (subclass ?MAT Plastic))) |
Sports.kif 1041-1048 |
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(subclass SnowSki TransportationDevice) | Sports.kif 1036-1036 | Ski is a subclass of transportation device |