题目内容：

There are many expressions with the word “dog”.

1. They take their dogs for walks, give them good food and medical care. However, dogs without owners to care for them lead a different kind of life. The expression, lead a dog’s life, describes a person who has an unhappy existence.

When we say we live in a dog-eat-dog world. 2. A person has to work hard like a dog to be successful. 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. 3. Yet, some people say that you can never teach an old dog new tricks. They believe that older people do not like to learn new skills and will not change the way they do things.

Some people are compared to dogs in bad ways. People who are unkind or uncaring can be described as junkyard dogs living in places where people throw away things they do not want. Junkyard dogs are often used to guard this property. They bark or attack people who try to enter the property. However, sometimes a person who appears to be mean and threatening is really not so bad. 4.

Dog expressions are also used to describe the weather. The dog days of summer are the hottest days of the year. 5. But we do not want it to rain cats and dogs.

A. Dogs are loyal to people.

B. A rainstorm may cool the weather.

C. People love dogs and treat them well.

D. We could say his bark is worse than his bite.

E. But there are many difficulties on the road to success.

F. To be successful, people often have to learn new skills.

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