sentences: an animal is a kind of living thing1 & if two things have the same features then those two things are alike ->  if two things have different features then those two things are different  if two things have different features then those two things are different & if things can be identified as different because of something then they are distinguishable by that something ->  things are distinguishable by their features  an animal is a kind of living thing0 & a bird is a kind of animal ->  a bird and a mammal are both kinds of animals  a bird and a mammal are both kinds of animals & an animal is a kind of living thing ->  a bird and a mammal are both kinds of things  things are distinguishable by their features & a bird and a mammal are both kinds of things ->  mammals and birds are distinguishable by their features  a bird is a kind of object & a mammal is a kind of object ->  a mammal is a kind of object and a bird is a kind of object  a mammal is a kind of object and a bird is a kind of object & the parts of an object are features of that object ->  the parts of a mammal / bird are features of the mammal / bird  feathers are a part of a bird & fur is usually part of a mammal ->  fur is a part of mammals and feathers are a part of birds  the parts of a mammal / bird are features of the mammal / bird & fur is a part of mammals and feathers are a part of birds ->  fur is a feature of mammals and feathers are a feature of birds  mammals and birds are distinguishable by their features & fur is a feature of mammals and feathers are a feature of birds -> fur can be used to distinguish mammals from birds