Today，by carefully choosing dog parents，humans have created many different kinds of dog Each kind has its own look and talents and its own role within human society.Here are three examples of "a dog's life" in the human world.
Today，many hospitals let specially trained dogs in to bring love and cheer to patients.Shaynee is a therapy（治疗）dog.She visits children who are in hospital.Dogs like Shaynee help patients feel calm and at peace which can be hard in a busy hospital.They help both children and adults stay strong during long hospital stays，and，some suggest，even help them get better.
Today some beagles（小猎犬）work in airports for the government They are part of the program called he Beagle Brigade.A beagle is good or the work because of its powerful nose，and ability to follow smells.The Beagle Brigade's job is to smell everything that comes into the country.They make officers notice illegal（非法的）fruits.vegetables，and other foods in luggage or in mail.The beagles do the job far better than any human could.
While some dogs are working hard others are free to spend their days resting and playing Across the world，many pet dogs are treated like children.Many have their own rooms and all the things a dog could want Some even have their own clothes.Many of these pets spend their days playing，learning to follow or even going to classes.Their owners give them the best，and enjoy doing so.
Whether as workers or objects of affection（钟情）dogs have become helpful to humans in many ways.There are plenty of advantages for the dog，too.Many kinds of wild dogs have nearly disappeared from the Earth.However，the domestic dog's special place as "man's best friend" has allowed it to survive （存活）in a human world.
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