Dogs are extremely useful animals, if they are trained properly they can be very intelligent. Dogs give assistance for people with disabilities, they search and rescue people, there are sniffer dogs to find illegal substances also they are great companions.
nothing is useful
If it is a guard dog it guards property, that is useful.
Useful is not a noun or a verb, it is an adjective. Adjectives are descriptive words used to describe nouns. For example, if you say, "the useful dog," useful is the adjective modifying dog, the noun.
A dog trainer is very useful in training a dog that hasn't been puppy trained yet. The trainer will teach the dogs tricks as well if you so desire. However, the most important part of training a dog is to potty train.
Yes so they have some obediance
A structure of small size, similar to that of a dog-house, but offering useful shelter for a human.
Dogs are used for police , racing , guarding houses
Humans have fingers and thumbs, useful for picking things up, where as cats and dogs only have pads.
It can be useful for finding clever and fast dogs.
Useful to what - all animals are the product of evolution and therefore part of the ecosystem and play a vital part in it.
Depending on what type of dog it is, it could generally be useful for companionship or for use as a guard dog. Other reasons people get dogs is because they are blind or deaf and need a dog to help them get along their daily routine.
Depends on what you mean by useful. a brain legs arms body and car home computer family job umm dog knowledge im sure there is more