题目内容：

Americans use many expressions with the word dog. People in the United States love their dogs and treat them well. They take their dogs for walks, let them play outside and give them good food and medical care. 1.The expression, to lead a dog’s life, describes a person who has an unhappy existence.

Some people say we live in a dog-eat-dog world.2.They say that to be successful, a person has to work like a dog. This means they have to work very, very hard. Such hard work can make people dog-tired. And, the situation would be even worse if they became sick as a dog.

Still, people say every dog has its day. This means that every person enjoys a successful period during his or her life. To be successful, people often have to learn new skills. Yet, some people say that you can never teach an old dog new tricks. 3.

Some people are compared to dogs in bad ways. People who are unkind or uncaring can be described as meaner than a junkyard dog. Husbands and wives use this doghouse term when they are angry at each other. For example, a woman might get angry at her husband for coming home late or forgetting their wedding anniversary. She might tell him that he is in the doghouse.4.

However, the husband may decide that it is best to leave things alone and not create more problems. He might decide to let sleeping dogs lie.

5.The dog days of summer are the hottest days of the year. A rainstorm may cool the weather. But we do not want it to rain too hard. We do not want it to rain cats and dogs.

A.She may not treat him nicely until he apologizes.

B.Dog expressions also are used to describe the weather.

C.They firmly belief that dogs are the best friends of human beings.

D.She will drop a line to remind him of it or ring him back at once.

E.However, dogs without owners to care for them lead a different kind of life.

F.That means many people are competing for the same things, like good jobs.

G.They believe that older people do not like to learn new things and will not change the way they do things.