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Americans love pets. In America, there are       families with pets than those with children.     is common that U.S. homes have some sorts of pets, such as monkeys, snakes and even wolves. But Americans’ all-time favorites are cats and dogs, because dogs can offer      (protect) from thieves and unwelcome visitors and cats can help get rid of the home unwanted pests. Beneath keeping pets, there lies    basic American belief: Pets have a right to be treated well. In Houston, Texas, dogs can have their dinner      (deliver) to their homes, just like pizza. Pets can even go with their owners on vacation. Besides, at least 75 animal welfare organizations exist in America    can provide care and adoption services for   (home) and ill-treated animals.      (pay) for the high-tech health care, people can buy health insurance for their pets. Pets are as basic to American culture      hot dogs or apple pie. By now researchers       (discover) that interacting with animals lowers a person’s blood pressure. Pets even encourage social relationships: They give their owners an appearance of friendliness, and they provide a good topic of conversation.