一篇关于“Dogs are people's friend"急!是现在时的围绕这几个问题：1 What can dogs do at home 2 Why do people keep dogs as pets?3 Who can dogs help?

Long ago,humankind started to tame animals.At first,the aim was probably just to use them:dogs to sniff for buried food; birds of prey to catch animals,also as food; horses to travel faster; oxen to pull ploughs; sheep to provide wool and meat; elephants to move heavy loads — the list is endless.From the 15th century on,“pointer” dogs were used in Europe to help hunters.In the 19th century in both North America and the British Isles “retriever” dogs were trained to help fishermen and hunters.
In the modern world,especially in the developed countries,pets can be a very important part of people’s lives.Old people can find their pets,especially dogs,a great comfort in their loneliness,old and young enjoy the beauty of goldfish swimming in bowls in their own homes,and young people often love to play with pets,especially small,furry ones!
A lot of families have pets,sometimes unusual ones.Pet shops in the West often sell animals like boas and stick insects.